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Author Meledin, A.; Turner, S.; Cayado, P.; Mundet, B.; Solano, E.; Ricart, S.; Ros, J.; Puig, T.; Obradors, X.; Van Tendeloo, G. url  doi
openurl 
  Title Unique nanostructural features in Fe, Mn-doped YBCO thin films Type A1 Journal article
  Year 2016 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 29 Issue 29 Pages 125009  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract An attempt to grow a thin epitaxial composite film of YBa2Cu3O7−δ (YBCO) with spinel MnFe2O4 (MFO) nanoparticles on a LAO substrate using the CSD approach resulted in a decomposition of the spinel and various doping modes of YBCO with the Fe and Mn cations. These nanostructural effects lead to a lowering of T c and a slight J c increase in field. Using a combination of advanced transmission electron microscopy (TEM) techniques such as atomic resolution high-angle annular dark field scanning TEM, energy dispersive x-ray spectroscopy and electron energy-loss spectroscopy we have been able to decipher and characterize the effects of the Fe and Mn doping on the film architecture. The YBaCuFeO5 anion-deficient double perovskite phase was detected in the form of 3D inclusions as well as epitaxially grown lamellas within the YBCO matrix. These nano-inclusions play a positive role as pinning centers responsible for the J c/J sf (H) dependency smoothening at high magnetic fields in the YBCO-MFO films with respect to the pristine YBCO films.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000387680100001 Publication Date 2016-10-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 6 Open Access  
  Notes The authors gratefully acknowledge Prof. Dr. A. Abakumov and Dr. J. Gazquez for discussions and corrections. Part of this work was performed within the framework of the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no. 280432), funded by the European Union. ICMAB research was financed by the Ministry of Economy and Competitiveness, and FEDER funds under the projects MAT2011-28874-C02-01, MAT2014-51778-C2-1-R, ENE2014-56109-C3-3-R and Consolider Nanoselect CSD2007-00041, and by Generalitat de Catalunya (2009 SGR 770, 2015 SGR 753 and Xarmae). ICMAB acknowledges support from Severo Ochoa Program (MINECO, Grant SEV-2015-0496). Approved (up) Most recent IF: 2.878  
  Call Number EMAT @ emat @ c:irua:136444 Serial 4295  
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Author Stafford, B.H.; Sieger, M.; Ottolinger, R.; Meledin, A.; Strickland, N.M.; Wimbush, S.C.; Van Tendeloo, G.; Huehne, R.; Schultz, L. pdf  doi
openurl 
  Title Tilted BaHfO3 nanorod artificial pinning centres in REBCO films on inclined substrate deposited-MgO coated conductor templates Type A1 Journal article
  Year 2017 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 30 Issue 5 Pages 055002  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We grow BaHfO3 (BHO) nanorods in REBa2Cu3O7-x (REBCO, RE: Gd or Y) thin films on metal tapes coated with the inclined substrate deposited (ISD)-MgO template by both electron beam physical vapour deposition and pulsed laser deposition. In both cases the nanorods are inclined by an angle of 21 degrees-29 degrees with respect to the sample surface normal as a consequence of the tilted growth of the REBCO film resulting from the ISD-MgO layer. We present angular critical current density (J(c)) anisotropy as well as field- and temperature-dependant J(c) data of the BHO nanorod-containing GdBCO films demonstrating an increase in J(c) over a wide range of temperatures between 30 and 77 K and magnetic fields up to 8 T. In addition, we show that the angle of the peak in the J(c) anisotropy curve resulting from the nanorods is dependent both on temperature and magnetic field. The largest J(c) enhancement from the addition of the nanorods was found to occur at 30 K, 3 T, resulting in a J(c) of 3.0 MA cm(-2).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000398860300001 Publication Date 2017-02-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 6 Open Access Not_Open_Access  
  Notes ; The authors would like to thank Anh Tu Bohn and other colleagues at THEVA Dunnschichtechnik GmbH for technical assistance and helpful discussion and R Nast for assistance with sample patterning. We also acknowledge partial support from EUROTAPES, a collaborative project funded by the European Commission's Seventh Framework Program (FP7/2007-2013) under Grant Agreement n. 280432. ; Approved (up) Most recent IF: 2.878  
  Call Number UA @ lucian @ c:irua:143641 Serial 4694  
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Author Pahlke, P.; Sieger, M.; Ottolinger, R.; Lao, M.; Eisterer, M.; Meledin, A.; Van Tendeloo, G.; Haenisch, J.; Holzapfel, B.; Schultz, L.; Nielsch, K.; Huehne, R. pdf  url
doi  openurl
  Title Influence of artificial pinning centers on structural and superconducting properties of thick YBCO films on ABAD-YSZ templates Type A1 Journal article
  Year 2018 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 31 Issue 4 Pages 044007  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Recent efforts in the development of YBa2Cu3O7-x (YBCO) coated conductors are devoted to the increase of the critical current I-c in magnetic fields. This is typically realized by growing thicker YBCO layers as well as by the incorporation of artificial pinning centers. We studied the growth of doped YBCO layers with a thickness of up to 7 mu m using pulsed laser deposition with a growth rate of about 1.2 nm s(-1). Industrially fabricated ion-beam textured YSZ templates based on metal tapes were used as substrates for this study. The incorporation of BaHfO3 (BHO) or Ba2Y(Nb0.5Ta0.5)O-6 (BYNTO) secondary phase additions leads to a denser microstructure compared to undoped films. A purely c-axis-oriented YBCO growth is preserved up to a thickness of about 4 mu m, whereas misoriented texture components were observed in thicker films. The critical temperature is slightly reduced compared to undoped films and independent of film thickness. The critical current density J(c) of the BHO- and BYNTO-doped YBCO layers is lower at 77 K and self-field compared to pure YBCO layers; however, I-c increases up to a thickness of 5 mu m. A comparison between films with a thickness of 1.3 mu m revealed that the anisotropy of the critical current density J(c)(theta) strongly depends on the incorporated pinning centers. Whereas BHO nanorods lead to a strong B vertical bar vertical bar c-axis peak, the overall anisotropy is significantly reduced by the incorporation of BYNTO forming a mixture of short c-axis-oriented nanorods and small (a-b)-oriented platelets. As a result, the J(c) values of the doped films outperform the undoped samples at higher fields and lower temperatures for most magnetic field directions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000442196400001 Publication Date 2018-02-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 9 Open Access OpenAccess  
  Notes ; The authors acknowledge financial support from EURO-TAPES, a collaborative project funded by the European Union's Seventh Framework Programme (FP7/ 2007-2013) under Grant Agreement no. 280432. We thank A Usoskin (Bruker HTS GmbH, Germany) for the provision of buffered templates, and M Bianchetti, A Kursumovic and J L Mac-Manus-Driscoll (University of Cambridge, UK) for the supply of BYNTO targets. The authors also gratefully acknowledge the technical assistance of J Scheiter, M Kuhnel, U Besold (IFW) and R Nast (KIT). ; Approved (up) Most recent IF: 2.878  
  Call Number UA @ lucian @ c:irua:153775 Serial 5108  
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Author Vasiliev, A.L.; Van Tendeloo, G.; Boikov, Y.; Olsson, E.; Ivanov, S. openurl 
  Title Microstructure of YBa2Cu3O7-x films on buffered Si for microelectronic applications Type A1 Journal article
  Year 1997 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 10 Issue Pages 356-365  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos A1997WY69100015 Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 2 Open Access  
  Notes Approved (up) Most recent IF: 2.878; 1997 IF: 2.183  
  Call Number UA @ lucian @ c:irua:21434 Serial 2076  
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Author Verbist, K.; Lebedev, O.I.; Verhoeven, M.A.J.; Winchern, R.; Rijnders, A.J.H.M.; Blank, D.H.A.; Tafuri, F.; Bender, H.; Van Tendeloo, G. pdf  doi
openurl 
  Title Microstructure of YBa2Cu3O7-\delta Josephson junctions in relation to their properties Type A1 Journal article
  Year 1998 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 11 Issue Pages 13-20  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000071820300005 Publication Date 2002-08-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited Open Access  
  Notes Approved (up) Most recent IF: 2.878; 1998 IF: 2.050  
  Call Number UA @ lucian @ c:irua:22112 Serial 2075  
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Author Tafuri, F.; Carillo, F.; Lombardi, F.; Granozio, F.M.; dii Uccio, U.S.; Testa, G.; Sarnelli, E.; Verbist, K.; Van Tendeloo, G. pdf  doi
openurl 
  Title YBa2Cu3O7-x Josephson junctions and dc SQUIDs based on 45\text{\textdegree} a-axis tilt and twist grain boundaries : atomically clean interfaces for applications Type A1 Journal article
  Year 1999 Publication Superconductor science and technology T2 – International Superconductive Electronics Conference, JUN 21-25, 1999, BERKELEY, CALIFORNIA Abbreviated Journal Supercond Sci Tech  
  Volume 12 Issue 11 Pages 1007-1009  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract YBa2Cu3O7-x artificial grain boundary Josephson junctions have been fabricated, employing a recently implemented biepitaxial technique. The grain boundaries can be obtained by controlling the orientation of the MgO seed layer and are characterized by a misalignment of the c-axes (45 degrees a-axis tilt or 45 degrees a-axis twist). These types of grain boundaries are still mostly unexplored. We carried out a complete characterization of their transport properties and microstructure. Junctions and de SQUIDs associated with these grain boundaries exhibit an excellent Josephson phenomenology and high values of the ICRN product and of the magnetic flux-to-voltage transfer parameter respectively. Remarkable differences in the transport parameters of tilt and twist junctions have been observed, which can be of interest for several applications. A maximum speed of Josephson vortices as calculated from the voltage step values of the order of 2 x 10(6) m s(-1) is obtained. These devices could also have some impact on experiments designed to study the symmetry of the order parameter, exploiting their microstructure and anisotropic properties. High-resolution electron microscopy showed the presence of perfect basal plane faced boundaries in the cross sections of tilt boundaries.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000083948400093 Publication Date 2002-08-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 3 Open Access  
  Notes Approved (up) Most recent IF: 2.878; 1999 IF: 1.728  
  Call Number UA @ lucian @ c:irua:102896 Serial 3565  
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Author Obradors, X.; Puig, T.; Pomar, A.; Sandiumenge, F.; Piñol, S.; Mestres, N.; Castaño, O.; Coll, M.; Cavallaro, A.; Palau, A.; Gázquez, J.; González, J.C.; Gutiérrez, J.; Romá, N.; Ricart, S.; Moretó, J.M.; Rossell, M.D.; Van Tendeloo, G. pdf  doi
openurl 
  Title Chemical solution deposition: a path towards low cost coated conductors Type A1 Journal article
  Year 2004 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 17 Issue 8 Pages 1055-1064  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000223574000022 Publication Date 2004-06-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 107 Open Access  
  Notes Approved (up) Most recent IF: 2.878; 2004 IF: 1.556  
  Call Number UA @ lucian @ c:irua:54870 Serial 350  
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Author Tan, H.; Lebedev, O.I.; McLaughlin, A.C.; Van Tendeloo, G. pdf  doi
openurl 
  Title The superstructure and superconductivity of Ru1222 based RuSr2Gd2-x-yYyCexCu2O10-\delta compounds Type A1 Journal article
  Year 2010 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 23 Issue 11 Pages 115013-115013,8  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract For the first time, the local structure and physical properties of Ru1222 based compounds (RuSr(2)Gd(1.4)Ce(0.6)Cu(2)O(10-delta) and RuSr(2)Gd(1.8-x)Y(0.2)CexCu(2)O(10) (x = 0.90-0.55)) have been investigated and analyzed together on the very same compounds. The Ru1222 superstructure was confirmed by TEM at a local scale and was suggested to have an orthorhombic symmetry with space group Aba2 and lattice parameters a(s) similar or equal to root 2a, b(s) similar or equal to root 2a and c(s) = c. This new Ru1222 superstructure distortion from tetragonal symmetry is proposed to have a positive correlation with the superconductivity variation of these compounds. The more the distortion towards orthorhombic symmetry, the higher the critical superconducting temperature these compounds can achieve. The T(c)(0) of RuSr(2)Gd(1.8-x)Y(0.2)Ce(x)Cu(2)O(10-delta) (x = 0.85-0.55) increases monotonically from 4 to 16 K when x decreases from 0.85 to 0.70, then RuSr(2)Gd(2)Cu(2)O(8) defects emerge and the T(c) decreases with decreasing x. Ru1212 defects are observed to intergrow epitaxially with the Ru1222 structure as lamellas along the c-axis in RuSr(2)Gd(1.4)Ce(0.6)Cu(2)O(10-delta). Although Ru1212 is a superconductor, the intergrowth severely restrains its superconductivity.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000284308000013 Publication Date 2010-10-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 1 Open Access  
  Notes Fwo; Esteem 026019 Approved (up) Most recent IF: 2.878; 2010 IF: 2.402  
  Call Number UA @ lucian @ c:irua:95553 Serial 3385  
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Author Molina, L.; Tan, H.; Biermans, E.; Batenburg, K.J.; Verbeeck, J.; Bals, S.; Van Tendeloo, G. pdf  doi
openurl 
  Title Barrier efficiency of sponge-like La2Zr2O7 buffer layers for YBCO-coated conductors Type A1 Journal article
  Year 2011 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 24 Issue 6 Pages 065019-065019,8  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract Solution derived La2Zr2O7 films have drawn much attention for potential applications as thermal barriers or low-cost buffer layers for coated conductor technology. Annealing and coating parameters strongly affect the microstructure of La2Zr2O7, but different film processing methods can yield similar microstructural features such as nanovoids and nanometer-sized La2Zr2O7 grains. Nanoporosity is a typical feature found in such films and the implications for the functionality of the films are investigated by a combination of scanning transmission electron microscopy (STEM), electron energy-loss spectroscopy (EELS) and quantitative electron tomography. Chemical solution based La2Zr2O7 films deposited on flexible Ni5 at.%W substrates with a {100}lang001rang biaxial texture were prepared for an in-depth characterization. A sponge-like structure composed of nanometer-sized voids is revealed by high-angle annular dark-field scanning transmission electron microscopy in combination with electron tomography. A three-dimensional quantification of nanovoids in the La2Zr2O7 film is obtained on a local scale. Mostly non-interconnected highly faceted nanovoids compromise more than one-fifth of the investigated sample volume. The diffusion barrier efficiency of a 170 nm thick La2Zr2O7 film is investigated by STEM-EELS, yielding a 1.8 ± 0.2 nm oxide layer beyond which no significant nickel diffusion can be detected and intermixing is observed. This is of particular significance for the functionality of YBa2Cu3O7 − δ coated conductor architectures based on solution derived La2Zr2O7 films as diffusion barriers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000290472900021 Publication Date 2011-04-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 31 Open Access  
  Notes Esteem 026019; Fwo Approved (up) Most recent IF: 2.878; 2011 IF: 2.662  
  Call Number UA @ lucian @ c:irua:88639UA @ admin @ c:irua:88639 Serial 221  
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Author Molina, L.; Egoavil, R.; Turner, S.; Thersleff, T.; Verbeeck, J.; Holzapfel, B.; Eibl, O.; Van Tendeloo, G. pdf  doi
openurl 
  Title Interlayer structure in YBCO-coated conductors prepared by chemical solution deposition Type A1 Journal article
  Year 2013 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 26 Issue 7 Pages 075016-75018  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The functionality of YBa2Cu3O7−δ (YBCO)-coated conductor technology depends on the reliability and microstructural properties of a given tape or wire architecture. Particularly, the interface to the metal tape is of interest since it determines the adhesion, mechanical stability of the film and thermal contact of the film to the substrate. A trifluoroacetate (TFA)metal organic deposition (MOD) prepared YBCO film deposited on a chemical solution-derived buffer layer architecture based on CeO2/La2Zr2O7 and grown on a flexible Ni5 at.%W substrate with a {100}⟨001⟩ biaxial texture was investigated. The YBCO film had a thickness was 440 nm and a jc of 1.02 MA cm−2 was determined at 77 K and zero external field. We present a sub-nanoscale analysis of a fully processed solution-derived YBCO-coated conductor by aberration-corrected scanning transmission electron microscopy (STEM) combined with electron energy-loss spectroscopy (EELS). For the first time, structural and chemical analysis of the valence has been carried out on the sub-nm scale. Intermixing of Ni, La, Ce, O and Ba takes place at these interfaces and gives rise to nanometer-sized interlayers which are a by-product of the sequential annealing process. Two distinct interfacial regions were analyzed in detail: (i) the YBCO/CeO2/La2Zr2O7 region (10 nm interlayer) and (ii) the La2Zr2O7/Ni5 at.%W substrate interface region (20 nm NiO). This is of particular significance for the functionality of these YBCO-coated conductor architectures grown by chemical solution deposition.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000319973800024 Publication Date 2013-05-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 11 Open Access  
  Notes vortex; Countatoms; Fwo; Esteem2; esteem2jra2; esteem2jra3 ECASJO_; Approved (up) Most recent IF: 2.878; 2013 IF: 2.796  
  Call Number UA @ lucian @ c:irua:108704UA @ admin @ c:irua:108704 Serial 1698  
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Author Wang, H.; Picot, T.; Houben, K.; Moorkens, T.; Grigg, J.; Van Haesendonck, C.; Biermans, E.; Bals, S.; Brown, S.A.; Vantomme, A.; Temst, K.; Van Bael, M.J.; pdf  doi
openurl 
  Title The superconducting proximity effect in epitaxial Al/Pb nanocomposites Type A1 Journal article
  Year 2014 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 27 Issue 1 Pages 015008-8  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We have investigated the superconducting properties of Pb nanoparticles with a diameter ranging from 8 to 20 nm, synthesized by Pb+ ion implantation in a crystalline Al matrix. A detailed structural characterization of the nanocomposites reveals the highly epitaxial relation between the Al crystalline matrix and the Pb nanoparticles. The Al/Pb nanocomposites display a single superconducting transition, with the critical temperature T-c increasing with the Pb content. The dependence of T-c on the Pb/Al volume ratio was compared with theoretical models of the superconducting proximity effect based on the bulk properties of Al and Pb. A very good correspondence with the strong-coupling proximity effect model was found, with an electron-phonon coupling constant in the Pb nanoparticles slightly reduced compared to bulk Pb. Our result differs from other studies on Pb nanoparticle based proximity systems where weak-coupling models were found to better describe the T-c dependence. We infer that the high interface quality resulting from the ion implantation synthesis method is a determining factor for the superconducting properties. Critical field and critical current measurements support the high quality of the nanocomposite superconducting films.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000328275000010 Publication Date 2013-11-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 2 Open Access Not_Open_Access  
  Notes ; This work was supported by the Research Foundation-Flanders (FWO), the KU Leuven BOF Concerted Research Action programs (GOA/09/006, the KU Leuven BOF CREA/12/015 project, and GOA/14/007) and the EU FP7 program SPIRIT (227012). TP and KH are postdoctoral research fellow and doctoral fellow of the FWO. ; Approved (up) Most recent IF: 2.878; 2014 IF: 2.325  
  Call Number UA @ lucian @ c:irua:112833 Serial 3599  
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Author Cayado, P.; De Keukeleere, K.; Garzón, A.; Perez-Mirabet, L.; Meledin, A.; De Roo, J.; Vallés, F.; Mundet, B.; Rijckaert, H.; Pollefeyt, G.; Coll, M.; Ricart, S.; Palau, A.; Gázquez, J.; Ros, J.; Van Tendeloo, G.; Van Driessche, I.; Puig, T.; Obradors, X. pdf  url
doi  openurl
  Title Epitaxial YBa2Cu3O7−xnanocomposite thin films from colloidal solutions Type A1 Journal article
  Year 2015 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 28 Issue 28 Pages 124007  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract A methodology of general validity to prepare epitaxial nanocomposite films based on the use of colloidal solutions containing different crystalline preformed oxide nanoparticles ( ex situ nanocomposites) is reported. The trifluoroacetate (TFA) metal–organic chemical solution deposition route is used with alcoholic solvents to grow epitaxial YBa 2 Cu 3 O 7 (YBCO) films. For this reason stabilizing oxide nanoparticles in polar solvents is a challenging goal. We have used scalable nanoparticle synthetic methodologies such as thermal and microwave-assisted solvothermal techniques to prepare CeO 2 and ZrO 2 nanoparticles. We show that stable and homogeneous colloidal solutions with these nanoparticles can be reached using benzyl alcohol, triethyleneglycol, nonanoic acid, trifluoroacetic acid or decanoic acid as protecting ligands, thereby allowing subsequent mixing with alcoholic TFA solutions. An elaborate YBCO film growth analysis of these nanocomposites allows the identification of the different relevant growth phenomena, e.g. nanoparticles pushing towards the film surface, nanoparticle reactivity, coarsening and nanoparticle accumulation at the substrate interface. Upon mitigation of these effects, YBCO nanocomposite films with high self-field critical currents ( J c ∼ 3–4 MA cm −2 at 77 K) were reached, indicating no current limitation effects associated with epitaxy perturbation, while smoothed magnetic field dependences of the critical currents at high magnetic fields and decreased effective anisotropic pinning behavior confirm the effectiveness of the novel developed approach to enhance vortex pinning. In conclusion, a novel low cost solution-derived route to high current nanocomposite superconducting films and coated conductors has been developed with very promising features.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000366288100009 Publication Date 2015-11-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 32 Open Access  
  Notes All authors acknowledge the EU (EU-FP7 NMP-LA-2012-280432 EUROTAPES project). ICMAB acknowledges MINECO (MAT2014-51778-C2-1-R) and Generalitat de Catalunya (2014SGR 753 and Xarmae). UGhent acknowledges the Special Research Fund (BOF), the Research Foundation Flanders (FWO) and the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT). TEM microscopy work was conducted in the Catalan Institute of Nanoscience and Nanotechnology (ICN2). The authors acknowledge the ICN2 Electron Microscopy Division for offering access to their instruments and expertise. Part of the STEM microscopy work was conducted in 'Laboratorio de Microscopias Avanzadas' at the Instituto de Nanociencia de Aragon—Universidad de Zaragoza. The authors acknowledge the LMA-INA for offering access to their instruments and expertise. JG and MC also acknowledge the Ramon y Cajal program (RYC-2012-11709 and RYC-2013-12448 respectively). Approved (up) Most recent IF: 2.878; 2015 IF: 2.325  
  Call Number c:irua:129593 Serial 3966  
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Author Molina-Luna, L.; Duerrschnabel, M.; Turner, S.; Erbe, M.; Martinez, G.T.; Van Aert, S.; Holzapfel, B.; Van Tendeloo, G. pdf  doi
openurl 
  Title Atomic and electronic structures of BaHfO3-doped TFA-MOD-derived YBa2Cu3O7−δthin films Type A1 Journal article
  Year 2015 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 28 Issue 28 Pages 115009  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Tailoring the properties of oxide-based nanocomposites is of great importance for a wide range of materials relevant for energy technology. YBa2Cu3O7−δ (YBCO) superconducting thin films containing nanosized BaHfO3 (BHO) particles yield a significant improvement of the magnetic flux pinning properties and a reduced anisotropy of the critical current density. These films were prepared by chemical solution deposition (CSD) on (100) SrTiO3 (STO) substrates yielding critical current densities up to 3.6 MA cm−2 at 77 K and self-field. Transport in-field J c measurements demonstrated a high pinning force maximum of around 6 GN/m3 for a sample annealed at T = 760 °C that has a doping of 12 mol% of BHO. This sample was investigated by scanning transmission electron microscopy (STEM) in combination with electron energy-loss spectroscopy (EELS) yielding strain and spectral maps. Spherical BHO nanoparticles of 15 nm in size were found in the matrix, whereas the particles at the interface were flat. A 2 nm diffusion layer containing Ti was found at the YBCO (BHO)/STO interface. Local lattice deformation mapping at the atomic scale revealed crystal defects induced by the presence of both sorts of BHO nanoparticles, which can act as pinning centers for magnetic flux lines. Two types of local lattice defects were identified and imaged: (i) misfit edge dislocations and (ii) Ba-Cu-Cu-Ba stacking faults (Y-248 intergrowths). The local electronic structure and charge transfer were probed by high energy resolution monochromated electron energy-loss spectroscopy. This technique made it possible to distinguish superconducting from non-superconducting areas in nanocomposite samples with atomic resolution in real space, allowing the identification of local pinning sites on the order of the coherence length of YBCO (~1.5 nm) and the determination of 0.25 nm dislocation cores.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000366193000018 Publication Date 2015-09-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 4 Open Access  
  Notes The authors thank financial support from the European Union under the Framework 6 program as a contract for an Integrated Infrastructure Initiative (References No. 026019 ESTEEM) and by the EUFP6 Research Project “NanoEngineered Superconductors for Power Applications” NESPA no. MRTN-CT-2006-035619. This work was supported by funding from the European Research Council under the Seventh Framework Programme (FP7). L.M.L, S.T. and G.V.T acknowledge ERC grant N°246791 – COUNTATOMS and funding under a contract for an Integrated Infrastructure Initiative, Reference No. 312483- ESTEEM2, as well as the EC project EUROTAPES. G.T.M. and S.V.A acknowledge financial support from the Fund for Scientific Research-Flanders (Reference G.0064.10N and G.0393.11N). M.D. acknowledges financial support from the LOEWE research cluster RESPONSE (Hessen, Germany). M.E. has received funding from the European Union Seventh Framework Programme (FP7/2007–2013) under grant agreement n° NMP-LA-2012-280432.; esteem2jra2; esteem2jra3 Approved (up) Most recent IF: 2.878; 2015 IF: 2.325  
  Call Number c:irua:129199 c:irua:129199 Serial 3942  
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Author Erbe, M.; Hänisch, J.; Hühne, R.; Freudenberg, T.; Kirchner, A.; Molina-Luna, L.; Damm, C.; Van Tendeloo, G.; Kaskel, S.; Schultz, L.; Holzapfel, B. pdf  doi
openurl 
  Title BaHfO3artificial pinning centres in TFA-MOD-derived YBCO and GdBCO thin films Type A1 Journal article
  Year 2015 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 28 Issue 28 Pages 114002  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Chemical solution deposition (CSD) is a promising way to realize REBa2Cu3O7−x (REBCO;RE = rare earth (here Y, Gd))-coated conductors with high performance in applied magnetic fields. However, the preparation process contains numerous parameters which need to be tuned to achieve high-quality films. Therefore, we investigated the growth of REBCO thin films containing nanometre-scale BaHfO3 (BHO) particles as pinning centres for magnetic flux lines, with emphasis on the influence of crystallization temperature and substrate on the microstructure and superconductivity. Conductivity, microscopy and x-ray investigations show an enhanced performance of BHO nano-composites in comparison to pristine REBCO. Further, those measurements reveal the superiority of GdBCO to YBCO—e.g. by inductive critical current densities, Jc, at self-field and 77 K. YBCO is outperformed by more than 1 MA cm−2 with Jc values of up to 5.0 MA cm−2 for 265 nm thick layers of GdBCO(BHO) on lanthanum aluminate. Transport in-field Jc measurements demonstrate high pinning force maxima of around 4 GN m−3 for YBCO(BHO) and GdBCO(BHO). However, the irreversibility fields are appreciably higher for GdBCO. The critical temperature was not significantly reduced upon BHO addition to both YBCO and GdBCO, indicating a low tendency for Hf diffusion into the REBCO matrix. Angular-dependent Jc measurements show a reduction of the anisotropy in the same order of magnitude for both REBCO compounds. Theoretical models suggest that more than one sort of pinning centre is active in all CSD films.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000366193000003 Publication Date 2015-09-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 36 Open Access  
  Notes Experimental work was mainly done at IFW Dresden. We thank Juliane Scheiter and Dr Jens Ingolf Mönch of IFW Dresden for technical assistance. The research leading to these results received funding from EUROTAPES, a collaborative project funded by the European Union Seventh Framework Programme (FP7/2007–2013) under grant agreement no. NMP-LA-2012-280 432. L Molina-Luna and G Van Tendeloo acknowledge funding from the European Research Council (ERC grant nr. 24 691-COUNTATOMS). Approved (up) Most recent IF: 2.878; 2015 IF: 2.325  
  Call Number c:irua:129200 Serial 3941  
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Author Nord, M.; Webster, R.W.H.; Paton, K.A.; McVitie, S.; McGrouther, D.; MacLaren, I.; Paterson, G.W. url  doi
openurl 
  Title Fast pixelated detectors in scanning transmission electron microscopy. Part I: data acquisition, live processing, and storage Type A1 Journal article
  Year 2020 Publication Microscopy And Microanalysis Abbreviated Journal Microsc Microanal  
  Volume 26 Issue 4 Pages Pii S1431927620001713-666  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The use of fast pixelated detectors and direct electron detection technology is revolutionizing many aspects of scanning transmission electron microscopy (STEM). The widespread adoption of these new technologies is impeded by the technical challenges associated with them. These include issues related to hardware control, and the acquisition, real-time processing and visualization, and storage of data from such detectors. We discuss these problems and present software solutions for them, with a view to making the benefits of new detectors in the context of STEM more accessible. Throughout, we provide examples of the application of the technologies presented, using data from a Medipix3 direct electron detector. Most of our software are available under an open source licence, permitting transparency of the implemented algorithms, and allowing the community to freely use and further improve upon them.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000555537900004 Publication Date 2020-07-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1431-9276 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.8 Times cited 4 Open Access OpenAccess  
  Notes ; The performance of this work was mainly supported by the Engineering and Physical Sciences Research Council (EPSRC) of the UK via the project “Fast Pixel Detectors: a paradigm shift in STEM imaging” (grant no. EP/M009963/1). G.W.P. received additional support from the EPSRC under grant no. EP/M024423/1. M.N. received additional support for this work from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 838001. The studentship of R.W.H.W. was supported by the EPSRC Doctoral Training Partnership grant no. EP/N509668/1. S.McV. was supported by EPSRC grant no. EP/M024423/1. I.M. was supported by EPSRC grant no. EP/M009963/1. The studentship of K.A.P. was funded entirely by the UK Science and Technology Facilities Council (STFC) Industrial CASE studentship “Next2 TEM Detection” (no. ST/P002471/1) with Quantum Detectors Ltd. as the industrial partner. D.McG. was also supported by EPSRC grant no. EP/M009963/1. As an inventor of intellectual property related to the MERLIN detector hardware, he is a beneficiary of the license agreement between the University of Glasgow and Quantum Detectors Ltd. The development of the integration of TopSpin with the Merlin readout of the Medipix3 camera has been performed with the aid of financial assistance from the EPSRC under grant no. EP/R511705/1 and through direct collaboration between NanoMEGAS and Quantum Detectors Ltd. ; Approved (up) Most recent IF: 2.8; 2020 IF: 1.891  
  Call Number UA @ admin @ c:irua:171185 Serial 6518  
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Author Paterson, G.W.; Webster, R.W.H.; Ross, A.; Paton, K.A.; Macgregor, T.A.; McGrouther, D.; MacLaren, I.; Nord, M. url  doi
openurl 
  Title Fast pixelated detectors in scanning transmission electron microscopy. part II : post-acquisition data processing, visualization, and structural characterization Type A1 Journal article
  Year 2020 Publication Microscopy And Microanalysis Abbreviated Journal Microsc Microanal  
  Volume 26 Issue 5 Pages 944-963  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Fast pixelated detectors incorporating direct electron detection (DED) technology are increasingly being regarded as universal detectors for scanning transmission electron microscopy (STEM), capable of imaging under multiple modes of operation. However, several issues remain around the post-acquisition processing and visualization of the often very large multidimensional STEM datasets produced by them. We discuss these issues and present open source software libraries to enable efficient processing and visualization of such datasets. Throughout, we provide examples of the analysis methodologies presented, utilizing data from a 256 x 256 pixel Medipix3 hybrid DED detector, with a particular focus on the STEM characterization of the structural properties of materials. These include the techniques of virtual detector imaging; higher-order Laue zone analysis; nanobeam electron diffraction; and scanning precession electron diffraction. In the latter, we demonstrate a nanoscale lattice parameter mapping with a fractional precision <= 6 x 10(-4) (0.06%).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000576859800011 Publication Date 2020-09-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1431-9276 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.8 Times cited 3 Open Access OpenAccess  
  Notes ; G.W.P. and M.N. were the principal authors of the fpd and pixStem libraries reported herein (details of all contributions are documented in the repositories) and have made all of these available under open source licence GPLv3 for the benefit of the community. R.W.H.W., A.R., and K.A.P. have also made contributions to the source codes in these libraries. G.W.P and M.N. have led the data acquisition and analysis, and the drafting of this manuscript. The performance of this work was mainly supported by Engineering and Physical Sciences Research Council (EPSRC) of the UK via the project “Fast Pixel Detectors: a paradigm shift in STEM imaging” (Grant No. EP/M009963/1). G.W.P. received additional support from the EPSRC under Grant No. EP/M024423/1. M.N. received additional support for this work from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 838001. R.W.H.W., A.R., K.A.P., T.A.M., D.McG., and I.M. have all contributed either through acquisition and analysis of data or through participation in the revision of the manuscript. The studentships of R.W.H.W. and T.A.M. were supported by the EPSRC Doctoral Training Partnership Grant No. EP/N509668/1. I.M. and D.McG. were supported by EPSRC Grant No. EP/M009963/1. The studentship of K.A.P. was funded entirely by the UK Science and Technology Facilities Council (STFC) Industrial CASE studentship “Next2 TEM Detection” (No. ST/ P002471/1) with Quantum Detectors Ltd. as the industrial partner. As an inventor of intellectual property related to the MERLIN detector hardware, D.McG. is a beneficiary of the license agreement between the University of Glasgow and Quantum Detectors Ltd. We thank Diamond Quantum Detectors Ltd. for Medipix3 detector support; Dr. Bruno Humbel from Okinawa Institute of Science and Technology; and Dr. Caroline Kizilyaprak from the University of Lausanne for providing the liver sample; Dr. Ingrid Hallsteinsen and Prof. Thomas Tybell from the Norwegian University of Science and Technology (NTNU) for providing the La0.7Sr0.3MnO3/LaFeO3/SrTiO3 sample shown in Figure 4; and NanoMEGAS for the loan of the DigiSTAR precession system and TopSpin acquisition software. The development of the integration of TopSpin with the Merlin readout of the Medipix3 camera has been performed with the aid of financial assistance from the EPSRC under Grant No. EP/R511705/1 and through direct collaboration between NanoMEGAS and Quantum Detectors Ltd. ; Approved (up) Most recent IF: 2.8; 2020 IF: 1.891  
  Call Number UA @ admin @ c:irua:172695 Serial 6519  
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Author Wang, J.; Nguyen, M.D.; Gauquelin, N.; Verbeeck, J.; Do, M.T.; Koster, G.; Rijnders, G.; Houwman, E. url  doi
openurl 
  Title On the importance of the work function and electron carrier density of oxide electrodes for the functional properties of ferroelectric capacitors Type A1 Journal article
  Year 2020 Publication Physica Status Solidi-Rapid Research Letters Abbreviated Journal Phys Status Solidi-R  
  Volume 14 Issue 14 Pages 1900520  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract It is important to understand the effect of the interfaces between the oxide electrode layers and the ferroelectric layer on the polarization response for optimizing the device performance of all-oxide ferroelectric devices. Herein, the effects of the oxide La0.07Ba0.93SnO3 (LBSO) as an electrode material in an PbZr0.52Ti0.48O3 (PZT) ferroelectric capacitor are compared with those of the more commonly used SrRuO3 (SRO) electrode. SRO (top)/PZT/SRO (bottom), SRO/PZT/LBSO, and SRO/PZT/2 nm SRO/LBSO devices are fabricated. Only marginal differences in crystalline properties, determined by X-ray diffraction and scanning transmission electron microscopy, are found. High-quality polarization loops are obtained, but with a much larger coercive field for the SRO/PZT/LBSO device. In contrast to the SRO/PZT/SRO device, the polarization decreases strongly with increasing field cycling. This fatigue problem can be remedied by inserting a 2 nm SRO layer between PZT and LBSO. It is argued that strongly increased charge injection into the PZT occurs at the bottom interface, because of the low PZT/LBSO interfacial barrier and the much lower carrier density in LBSO, as compared with that in SRO, causing a low dielectric constant, depleted layer in LBSO. The charge injection creates a trapped space charge in the PZT, causing the difference in fatigue behavior.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000506195600001 Publication Date 2019-12-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1862-6254 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.8 Times cited 6 Open Access OpenAccess  
  Notes ; This work was supported by Nederlandse Organisatie voor Wetenschappelijk Onderzoek through grant no.13HTSM01. ; Approved (up) Most recent IF: 2.8; 2020 IF: 3.032  
  Call Number UA @ admin @ c:irua:165681 Serial 6316  
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Author Friedrich, T.; Yu, C.-P.; Verbeeck, J.; Van Aert, S. url  doi
openurl 
  Title Phase object reconstruction for 4D-STEM using deep learning Type A1 Journal article
  Year 2023 Publication Microscopy and microanalysis Abbreviated Journal  
  Volume 29 Issue 1 Pages 395-407  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract In this study, we explore the possibility to use deep learning for the reconstruction of phase images from 4D scanning transmission electron microscopy (4D-STEM) data. The process can be divided into two main steps. First, the complex electron wave function is recovered for a convergent beam electron diffraction pattern (CBED) using a convolutional neural network (CNN). Subsequently, a corresponding patch of the phase object is recovered using the phase object approximation. Repeating this for each scan position in a 4D-STEM dataset and combining the patches by complex summation yields the full-phase object. Each patch is recovered from a kernel of 3x3 adjacent CBEDs only, which eliminates common, large memory requirements and enables live processing during an experiment. The machine learning pipeline, data generation, and the reconstruction algorithm are presented. We demonstrate that the CNN can retrieve phase information beyond the aperture angle, enabling super-resolution imaging. The image contrast formation is evaluated showing a dependence on the thickness and atomic column type. Columns containing light and heavy elements can be imaged simultaneously and are distinguishable. The combination of super-resolution, good noise robustness, and intuitive image contrast characteristics makes the approach unique among live imaging methods in 4D-STEM.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001033590800038 Publication Date 2023-01-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1431-9276 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.8 Times cited 1 Open Access OpenAccess  
  Notes We acknowledge funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement no. 770887 PICOMETRICS) and funding from the European Union's Horizon 2020 research and innovation program under grant agreement No. 823717 ESTEEM3. J.V. and S.V.A acknowledge funding from the University of Antwerp through a TOP BOF project. The direct electron detector (Merlin, Medipix3, Quantum Detectors) was funded by the Hercules fund from the Flemish Government. This work was supported by the FWO and FNRS within the 2Dto3D project of the EOS program (grant number 30489208). Approved (up) Most recent IF: 2.8; 2023 IF: 1.891  
  Call Number UA @ admin @ c:irua:198221 Serial 8912  
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Author Juchtmans, R.; Verbeeck, J. url  doi
openurl 
  Title Local orbital angular momentum revealed by spiral-phase-plate imaging in transmission-electron microscopy Type A1 Journal article
  Year 2016 Publication Physical Review A Abbreviated Journal Phys Rev A  
  Volume 93 Issue 93 Pages 023811  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The orbital angular momentum (OAM) of light and matter waves is a parameter that has been getting increasingly more attention over the past couple of years. Beams with a well-defined OAM, the so-called vortex beams, are applied already in, e.g., telecommunication, astrophysics, nanomanipulation, and chiral measurements in optics and electron microscopy. Also, the OAM of a wave induced by the interaction with a sample has attracted a lot of interest. In all these experiments it is crucial to measure the exact (local) OAM content of the wave, whether it is an incoming vortex beam or an exit wave after interacting with a sample. In this work we investigate the use of spiral phase plates (SPPs) as an alternative to the programmable phase plates used in optics to measure OAM. We derive analytically how these can be used to study the local OAM components of any wave function. By means of numerical simulations we illustrate how the OAM of a pure vortex beam can be measured. We also look at a sum of misaligned vortex beams and show how, by using SPPs, the position and the OAM of each individual beam can be detected. Finally, we look at the OAM induced by a magnetic dipole on a free-electron wave and show how the SPP can be used to localize the magnetic poles and measure their “magnetic charge.” Although our findings can be applied to study the OAM of any wave function, our findings are of particular interest for electron microscopy where versatile programmable phase plates do not yet exist.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000369367700006 Publication Date 2016-02-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.925 Times cited 12 Open Access  
  Notes The authors acknowledge support from the Aspirant Fonds Wetenschappelijk Onderzoek–Vlaanderen (FPO), the EU un- der the Seventh Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative, Reference No. 312483- ESTEEM2, and the ERC Starting Grant 278510 VORTEX.; esteem2jra2 ECASJO; Approved (up) Most recent IF: 2.925  
  Call Number c:irua:131613 c:irua:131613UA @ admin @ c:irua:131613 Serial 4030  
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Author Clark, L.; Guzzinati, G.; Béché, A.; Lubk, A.; Verbeeck, J. pdf  url
doi  openurl
  Title Symmetry-constrained electron vortex propagation Type A1 Journal article
  Year 2016 Publication Physical review A Abbreviated Journal Phys Rev A  
  Volume 93 Issue 93 Pages 063840  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Electron vortex beams hold great promise for development in transmission electron microscopy but have yet to be widely adopted. This is partly due to the complex set of interactions that occur between a beam carrying orbital angular momentum (OAM) and a sample. Herein, the system is simplified to focus on the interaction between geometrical symmetries, OAM, and topology. We present multiple simulations alongside experimental data to study the behavior of a variety of electron vortex beams after interacting with apertures of different symmetries and investigate the effect on their OAM and vortex structure, both in the far field and under free-space propagation.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000378197200006 Publication Date 2016-06-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9926 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.925 Times cited 7 Open Access  
  Notes L.C., A.B., G.G., and J.V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant No. 278510—VORTEX. J.V. and A.L. acknowledge financial support from the European Union through the 7th Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2). The Qu-Ant-EM microscope was partly funded by the Hercules fund of the Flemish Government.; esteem2jra3; ECASJO; Approved (up) Most recent IF: 2.925  
  Call Number c:irua:134086 c:irua:134086 Serial 4090  
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Author Juchtmans, R.; Guzzinati, G.; Verbeeck, J. url  doi
openurl 
  Title Extension of Friedel's law to vortex-beam diffraction Type A1 Journal article
  Year 2016 Publication Physical Review A Abbreviated Journal Phys Rev A  
  Volume 94 Issue 94 Pages 033858  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Friedel's law states that the modulus of the Fourier transform of real functions is centrosymmetric, while the phase is antisymmetric. As a consequence of this, elastic scattering of plane-wave photons or electrons within the first-order Born-approximation, as well as Fraunhofer diffraction on any aperture, is bound to result in centrosymmetric diffraction patterns. Friedel's law, however, does not apply for vortex beams, and centrosymmetry in general is not present in their diffraction patterns. In this work we extend Friedel's law for vortex beams by showing that the diffraction patterns of vortex beams with opposite topological charge, scattered on the same two-dimensional potential, always are centrosymmetric to one another, regardless of the symmetry of the scattering object. We verify our statement by means of numerical simulations and experimental data. Our research provides deeper understanding in vortex-beam diffraction and can be used to design new experiments to measure the topological charge of vortex beams with diffraction gratings or to study general vortex-beam diffraction.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000384374500010 Publication Date 2016-09-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9926 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.925 Times cited 13 Open Access  
  Notes The authors acknowledge support from the FWO (Aspirant Fonds Wetenschappelijk Onderzoek – Vlaanderen) and the EU under the Seventh Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative, Reference No. 312483-ESTEEM2 and ERC Starting Grant No. 278510 VORTEX.; ECASJO_; Approved (up) Most recent IF: 2.925  
  Call Number EMAT @ emat @ c:irua:137200UA @ admin @ c:irua:137200 Serial 4314  
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Author Juchtmans, R.; Clark, L.; Lubk, A.; Verbeeck, J. url  doi
openurl 
  Title Spiral phase plate contrast in optical and electron microscopy Type A1 Journal article
  Year 2016 Publication Physical review A Abbreviated Journal Phys Rev A  
  Volume 94 Issue 94 Pages 023838  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The use of phase plates in the back focal plane of a microscope is a well-established technique in optical microscopy to increase the contrast of weakly interacting samples and is gaining interest in electron microscopy as well. In this paper we study the spiral phase plate (SPP), also called helical, vortex, or two-dimensional Hilbert phase plate, which adds an angularly dependent phase of the form exp(iℓϕk) to the exit wave in Fourier space. In the limit of large collection angles, we analytically calculate that the average of a pair of l=+-1

SPP filtered images is directly proportional to the gradient squared of the exit wave, explaining the edge contrast previously seen in optical SPP work. We discuss the difference between a clockwise-anticlockwise pair of SPP filtered images and derive conditions under which the modulus of the wave's gradient can be seen directly from one SPP filtered image. This work provides the theoretical background to interpret images obtained with a SPP, thereby opening new perspectives for new experiments to study, for example, magnetic materials in an electron microscope.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000381882800011 Publication Date 2016-08-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9926 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.925 Times cited 10 Open Access  
  Notes The authors acknowledge support from the FWO (Aspirant Fonds Wetenschappelijk Onderzoek – Vlaanderen) and the EU under the Seventh Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative, Reference No. 312483-ESTEEM2 and ERC Starting Grant No. 278510 VORTEX.; ECASJO_ Approved (up) Most recent IF: 2.925  
  Call Number EMAT @ emat @ c:irua:140086 Serial 4418  
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Author Lubk, A.; Clark, L.; Guzzinati, G.; Verbeeck, J. url  doi
openurl 
  Title Topological analysis of paraxially scattered electron vortex beams Type A1 Journal article
  Year 2013 Publication Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A  
  Volume 87 Issue 3 Pages 033834-33838  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We investigate topological aspects of subnanometer electron vortex beams upon elastic propagation through atomic scattering potentials. Two main aspects can be distinguished: (i) significantly reduced delocalization compared to a similar nonvortex beam if the beam centers on an atomic column and (ii) site symmetry dependent splitting of higher-order vortex beams. Furthermore, the results provide insight into the complex vortex line fabric within the elastically scattered wave containing characteristic vortex loops predominantly attached to atomic columns and characteristic twists of vortex lines around atomic columns. DOI: 10.1103/PhysRevA.87.033834  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos 000316790600011 Publication Date 2013-03-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.925 Times cited 26 Open Access  
  Notes Countatoms; Vortex; Esteem2; esteem2jra3 ECASJO; Approved (up) Most recent IF: 2.925; 2013 IF: 2.991  
  Call Number UA @ lucian @ c:irua:108496 Serial 3673  
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Author Guzzinati, G.; Clark, L.; Béché, A.; Verbeeck, J. url  doi
openurl 
  Title Measuring the orbital angular momentum of electron beams Type A1 Journal article
  Year 2014 Publication Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A  
  Volume 89 Issue Pages 025803  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The recent demonstration of electron vortex beams has opened up the new possibility of studying orbital angular momentum (OAM) in the interaction between electron beams and matter. To this aim, methods to analyze the OAM of an electron beam are fundamentally important and a necessary next step. We demonstrate the measurement of electron beam OAM through a variety of techniques. The use of forked holographic masks, diffraction from geometric apertures, and diffraction from a knife edge and the application of an astigmatic lens are all experimentally demonstrated. The viability and limitations of each are discussed with supporting numerical simulations.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000332224100014 Publication Date 2014-02-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.925 Times cited 42 Open Access  
  Notes Vortex; FP7; Countatoms; ESTEEM2; esteem2jra3 ECASJO; Approved (up) Most recent IF: 2.925; 2014 IF: 2.808  
  Call Number UA @ lucian @ c:irua:114577UA @ admin @ c:irua:114577 Serial 1972  
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Author Clark, L.; Béché, A.; Guzzinati, G.; Verbeeck, J. url  doi
openurl 
  Title Quantitative measurement of orbital angular momentum in electron microscopy Type A1 Journal article
  Year 2014 Publication Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A  
  Volume 89 Issue 5 Pages 053818  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Electron vortex beams have been predicted to enable atomic scale magnetic information measurement, via transfer of orbital angular momentum. Research so far has focused on developing production techniques and applications of these beams. However, methods to measure the outgoing orbital angular momentum distribution are also a crucial requirement towards this goal. Here, we use a method to obtain the orbital angular momentum decomposition of an electron beam, using a multipinhole interferometer. We demonstrate both its ability to accurately measure orbital angular momentum distribution, and its experimental limitations when used in a transmission electron microscope.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000335826300012 Publication Date 2014-05-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.925 Times cited 23 Open Access  
  Notes 7th Framework Program (FP7); ERC Starting Grant No. 278510- VORTEX 7th Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2). 7th Framework Program (FP7), ERC Grant No. 246791- COUNTATOMS. SP – 053818-1; esteem2jra3 ECASJO; Approved (up) Most recent IF: 2.925; 2014 IF: 2.808  
  Call Number UA @ lucian @ c:irua:117093UA @ admin @ c:irua:117093 Serial 2758  
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Author Van Boxem, R.; Partoens, B.; Verbeeck, J. url  doi
openurl 
  Title Rutherford scattering of electron vortices Type A1 Journal article
  Year 2014 Publication Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A  
  Volume 89 Issue 3 Pages 032715-32719  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract By considering a cylindrically symmetric generalization of a plane wave, the first-order Born approximation of screened Coulomb scattering unfolds two new dimensions in the scattering problem: transverse momentum and orbital angular momentum of the incoming beam. In this paper, the elastic Coulomb scattering amplitude is calculated analytically for incoming Bessel beams. This reveals novel features occurring for wide-angle scattering and quantitative insights for small-angle vortex scattering. The result successfully generalizes the well-known Rutherford formula, incorporating transverse and orbital angular momentum into the formalism.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000333690500008 Publication Date 2014-03-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.925 Times cited 34 Open Access  
  Notes 312483-Esteem2; N246791 – Countatoms; 278510 Vortex; esteem2jra1; esteem2jra3 ECASJO_; Approved (up) Most recent IF: 2.925; 2014 IF: 2.808  
  Call Number UA @ lucian @ c:irua:115562UA @ admin @ c:irua:115562 Serial 2936  
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Author Van Boxem, R.; Partoens, B.; Verbeeck, J. url  doi
openurl 
  Title Inelastic electron-vortex-beam scattering Type A1 Journal article
  Year 2015 Publication Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A  
  Volume 91 Issue 91 Pages 032703  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract Recent theoretical and experimental developments in the field of electron-vortex-beam physics have raised questions about what exactly this novelty in the field of electron microscopy (and other fields, such as particle physics) really provides. An important part of the answer to these questions lies in scattering theory. The present investigation explores various aspects of inelastic quantum scattering theory for cylindrically symmetric beams with orbital angular momentum. The model system of Coulomb scattering on a hydrogen atom provides the setting to address various open questions: How is momentum transferred? Do vortex beams selectively excite atoms, and how can one employ vortex beams to detect magnetic transitions? The analytical approach presented here provides answers to these questions. OAM transfer is possible, but not through selective excitation; rather, by pre- and postselection one can filter out the relevant contributions to a specific signal.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000351035000004 Publication Date 2015-03-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.925 Times cited 31 Open Access  
  Notes Fwo; 312483 Esteem2; 278510 Vortex; esteem2jra3 ECASJO; Approved (up) Most recent IF: 2.925; 2015 IF: 2.808  
  Call Number c:irua:123925 c:irua:123925UA @ admin @ c:irua:123925 Serial 1607  
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Author Nivesanond, K.; Peeters, A.; Lamoen, D.; van Alsenoy, C. doi  openurl
  Title Ab initio calculation of the interaction energy in the P2 binding pocket of HIV-1 protease Type A1 Journal article
  Year 2005 Publication International Journal Of Quantum Chemistry Abbreviated Journal Int J Quantum Chem  
  Volume 105 Issue 3 Pages 292-299  
  Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000232232300009 Publication Date 2005-07-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0020-7608;1097-461X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.92 Times cited 8 Open Access  
  Notes Approved (up) Most recent IF: 2.92; 2005 IF: 1.192  
  Call Number UA @ lucian @ c:irua:54919 Serial 30  
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Author Debroye, E.; Yuan, H.; Bladt, E.; Baekelant, W.; Van der Auweraer, M.; Hofkens, J.; Bals, S.; Roeffaers, M.B.J. url  doi
openurl 
  Title Facile morphology-controlled synthesis of organolead iodide perovskite nanocrystals using binary capping agents Type A1 Journal article
  Year 2017 Publication ChemNanoMat : chemistry of nanomaterials for energy, biology and more Abbreviated Journal Chemnanomat  
  Volume 3 Issue 3 Pages 223-227  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Controlling the morphology of organolead halide perovskite crystals is crucial to a fundamental understanding of the materials and to tune their properties for device applications. Here, we report a facile solution-based method for morphology-controlled synthesis of rod-like and plate-like organolead halide perovskite nanocrystals using binary capping agents. The morphology control is likely due to an interplay between surface binding kinetics of the two capping agents at different crystal facets. By high-resolution scanning transmission electron microscopy, we show that the obtained nanocrystals are monocrystalline. Moreover, long photoluminescence decay times of the nanocrystals indicate long charge diffusion lengths and low trap/defect densities. Our results pave the way for large-scale solution synthesis of organolead halide perovskite nanocrystals with controlled morphology for future device applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000399604300003 Publication Date 2017-01-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2199-692x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.937 Times cited 19 Open Access OpenAccess  
  Notes ; We acknowledge financial support from the Research Foundation-Flanders (FWO, grant G.0197.11, G.0962.13, G0B39.15, postdoctoral fellowship to E. D. and H. Y.), KU Leuven Research Fund (C14/15/053), the Flemish government through long term structural funding Methusalem (CASAS2, Meth/15/04), the Hercules foundation (HER/11/14), the Belgian Federal Science Policy Office (IAP-PH05), the EC through the Marie Curie ITN project iSwitch (GA-642196) and the ERC project LIGHT (GA307523). S. B. acknowledges financial support from European Research Council (ERC Starting Grant # 335078-COLOURATOMS). E. B. gratefully acknowledges financial support by the Flemish Fund for Scientific Research (FWO Vlaanderen). ; ecas_Sara Approved (up) Most recent IF: 2.937  
  Call Number UA @ lucian @ c:irua:143678UA @ admin @ c:irua:143678 Serial 4656  
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Author Berthold, T.; Castro, C.R.; Winter, M.; Hoerpel, G.; Kurttepeli, M.; Bals, S.; Antonietti, M.; Fechler, N. pdf  url
doi  openurl
  Title Tunable nitrogen-doped carbon nanoparticles from tannic acid and urea and their potential for sustainable soots Type A1 Journal article
  Year 2017 Publication ChemNanoMat : chemistry of nanomaterials for energy, biology and more Abbreviated Journal Chemnanomat  
  Volume 3 Issue 3 Pages 311-318  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Nano-sized nitrogen-doped carbon spheres are synthesized from two cheap, readily available and sustainable precursors: tannic acid and urea. In combination with a polymer structuring agent, nitrogen content, sphere size and the surface (up to 400 m(2)g(-1)) can be conveniently tuned by the precursor ratio, temperature and structuring agent content. Because the chosen precursors allow simple oven synthesis and avoid harsh conditions, this carbon nanosphere platform offers a more sustainable alternative to classical soots, for example, as printing pigments or conduction soots. The carbon spheres are demonstrated to be a promising as conductive carbon additive in anode materials for lithium ion batteries.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000403299200006 Publication Date 2017-03-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2199-692x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.937 Times cited 14 Open Access OpenAccess  
  Notes ; S.B. is grateful for funding by the European Research Council (ERC starting grant # 335078-COLOURATOMS). ; ecas_Sara Approved (up) Most recent IF: 2.937  
  Call Number UA @ lucian @ c:irua:144287UA @ admin @ c:irua:144287 Serial 4699  
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