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“Event driven 4D STEM acquisition with a Timepix3 detector: Microsecond dwell time and faster scans for high precision and low dose applications”. Jannis D, Hofer C, Gao C, Xie X, Béché, A, Pennycook Tj, Verbeeck J, Ultramicroscopy 233, 113423 (2022). http://doi.org/10.1016/j.ultramic.2021.113423
Abstract: Four dimensional scanning transmission electron microscopy (4D STEM) records the scattering of electrons in a material in great detail. The benefits offered by 4D STEM are substantial, with the wealth of data it provides facilitating for instance high precision, high electron dose efficiency phase imaging via centre of mass or ptychography based analysis. However the requirement for a 2D image of the scattering to be recorded at each probe position has long placed a severe bottleneck on the speed at which 4D STEM can be performed. Recent advances in camera technology have greatly reduced this bottleneck, with the detection efficiency of direct electron detectors being especially well suited to the technique. However even the fastest frame driven pixelated detectors still significantly limit the scan speed which can be used in 4D STEM, making the resulting data susceptible to drift and hampering its use for low dose beam sensitive applications. Here we report the development of the use of an event driven Timepix3 direct electron camera that allows us to overcome this bottleneck and achieve 4D STEM dwell times down to 100 ns; orders of magnitude faster than what has been possible with frame based readout. We characterize the detector for different acceleration voltages and show that the method is especially well suited for low dose imaging and promises rich datasets without compromising dwell time when compared to conventional STEM imaging.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 2.2
Times cited: 31
DOI: 10.1016/j.ultramic.2021.113423
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“Dynamical diffraction of high-energy electrons investigated by focal series momentum-resolved scanning transmission electron microscopy at atomic resolution”. Robert Hl, Lobato I, Lyu Fj, Chen Q, Van Aert S, Van Dyck D, Müller-Caspary K, Ultramicroscopy 233, 113425 (2022). http://doi.org/10.1016/j.ultramic.2021.113425
Abstract: We report a study of scattering dynamics in crystals employing momentum-resolved scanning transmission
electron microscopy under varying illumination conditions. As we perform successive changes of the probe
focus, multiple real-space signals are obtained in dependence of the shape of the incident electron wave.
With support from extensive simulations, each signal is shown to be characterised by an optimum focus for
which the contrast is maximum and which differs among different signals. For instance, a systematic focus
mismatch is found between images formed by high-angle scattering, being sensitive to thickness and chemical
composition, and the first moment in diffraction space, being sensitive to electric fields. It follows that a single
recording at one specific probe focus is usually insufficient to characterise materials comprehensively. Most
importantly, we demonstrate in experiment and simulation that the second moment (
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Impact Factor: 2.2
DOI: 10.1016/j.ultramic.2021.113425
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“Reducing electron beam damage through alternative STEM scanning strategies, Part II: Attempt towards an empirical model describing the damage process”. Jannis D, Velazco A, Béché, A, Verbeeck J, Ultramicroscopy , 113568 (2022). http://doi.org/10.1016/j.ultramic.2022.113568
Abstract: In this second part of a series we attempt to construct an empirical model that can mimick all experimental observations made regarding the role of an alternative interleaved scan pattern in STEM imaging on the beam damage in a specific zeolite sample. We make use of a 2D diffusion model that describes the dissipation of the deposited beam energy in the sequence of probe positions that are visited during the scan pattern. The diffusion process allows for the concept of trying to ‘outrun’ the beam damage by carefully tuning the dwell time and distance between consecutively visited probe positions. We add a non linear function to include a threshold effect and evaluate the accumulated damage in each part of the image as a function of scan pattern details. Together, these ingredients are able to describe qualitatively all aspects of the experimental data and provide us with a model that could guide a further optimisation towards even lower beam damage without lowering the applied electron dose. We deliberately remain vague on what is diffusing here which avoids introducing too many sample specific details. This provides hope that the model can be applied also in sample classes that were not yet studied in such great detail by adjusting higher level parameters: a sample dependent diffusion constant and damage threshold.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 2.2
Times cited: 4
DOI: 10.1016/j.ultramic.2022.113568
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“Optimal experiment design for element specific atom counting using multiple annular dark field scanning transmission electron microscopy detectors”. Sentürk DG, De Backer A, Friedrich T, Van Aert S, Ultramicroscopy 242, 113626 (2022). http://doi.org/10.1016/j.ultramic.2022.113626
Abstract: This paper investigates the possible benefits for counting atoms of different chemical nature when analysing multiple 2D scanning transmission electron microscopy (STEM) images resulting from independent annular dark field (ADF) detector regimes. To reach this goal, the principles of statistical detection theory are used to quantify the probability of error when determining the number of atoms in atomic columns consisting of multiple types of elements. In order to apply this theory, atom-counting is formulated as a statistical hypothesis test, where each hypothesis corresponds to a specific number of atoms of each atom type in an atomic column. The probability of error, which is limited by the unavoidable presence of electron counting noise, can then be computed from scattering-cross sections extracted from multiple ADF STEM images. Minimisation of the probability of error as a function of the inner and outer angles of a specified number of independent ADF collection regimes results in optimal experimental designs. Based on simulations of spherical Au@Ag and Au@Pt core–shell nanoparticles, we investigate how the combination of two non-overlapping detector regimes helps to improve the probability of error when unscrambling two types of atoms. In particular, the combination of a narrow low angle ADF detector with a detector formed by the remaining annular collection regime is found to be optimal. The benefit is more significant if the atomic number Z difference becomes larger. In
addition, we show the benefit of subdividing the detector regime into three collection areas for heterogeneous nanostructures based on a structure consisting of three types of elements, e.g., a mixture of Au, Ag and Al atoms. Finally, these results are compared with the probability of error resulting when one would ultimately use a pixelated 4D STEM detector and how this could help to further reduce the incident electron dose.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.2
DOI: 10.1016/j.ultramic.2022.113626
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“Effect of substitutional impurities on the electronic transport properties of graphene”. Berdiyorov GR, Bahlouli H, Peeters FM, Physica. E: Low-dimensional systems and nanostructures 84, 22 (2016). http://doi.org/10.1016/j.physe.2016.05.024
Abstract: Density-functional theory in combination with the nonequilibrium Green's function formalism is used to study the effect of substitutional doping on the electronic transport properties of hydrogen passivated zig-zag graphene nanoribbon devices. B, N and Si atoms are used to substitute carbon atoms located at the center or at the edge of the sample. We found that Si -doping results in better electronic transport as compared to the other substitutions. The transmission spectrum also depends on the location of the substitutional dopants: for single atom doping the largest transmission is obtained for edge substitutions, whereas substitutions in the middle of the sample give larger transmission for double carbon substitutions. The obtained results are explained in terms of electron localization in the system due to the presence of impurities. (C) 2016 Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 17
DOI: 10.1016/j.physe.2016.05.024
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“Wave packet propagation through branched quantum rings under applied magnetic fields”. de Sousa AA, Chaves A, Pereira TAS, de Farias GA, Peeters FM, Physica. E: Low-dimensional systems and nanostructures 114, 113598 (2019). http://doi.org/10.1016/J.PHYSE.2019.113598
Abstract: We investigate the effect of opening and closing pathways on the dynamics of electron wave packets in semiconductor quantum rings with different geometries. Our analysis is based on the time evolution of an electron wave packet, within the effective-mass approximation. We demonstrate that opening an extra channel in the quantum ring does not necessarily improve the electron transmission and, depending on the extra channel width, may even reduce it, either due to enhancement of quantum scattering or due to interference. In the latter case, transmission reduction can be controlled through the Aharonov-Bohm phase of the wave function, via an applied magnetic field. It is also shown that, closing one of the channels of the quantum ring, system improves the transmission probability under specific conditions, an effect which is a quantum analog of the Braess paradox.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 2.221
DOI: 10.1016/J.PHYSE.2019.113598
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“Theoretical prediction of the PtOX (X = S and Se) monolayers as promising optoelectronic and thermoelectric 2D materials”. Nguyen DK, Hoat DM, Bafekry A, Van On V, Rivas-Silva JF, Naseri M, Cocoletzi GH, Physica E-Low-Dimensional Systems &, Nanostructures 131, 114732 (2021). http://doi.org/10.1016/J.PHYSE.2021.114732
Abstract: In this paper, two new monolayers, namely PtOS and PtOSe, are theoretically predicted using first-principles calculations. Structural, electronic, optical and thermoelectric properties are explored using full-potential linearized augmented plane-wave (FP-LAPW) method and the semiclassical Boltzmann transport theory. Predicted two-dimensional (2D) materials show good dynamical, thermodynamic and structural stability. Calculated electronic structures indicate the indirect gap semiconductor nature of the PtOS and PtOSe single layers with energy gap of 1.346(2.436) and 0.978(1.978) eV as calculated with the WC(HSE06) functional, respectively. Density of states spectra and valence charge distribution maps suggest a mix of covalent and ionic characters of the chemical bonds. 2D materials at hand exhibit good absorption property in the visible regime with coefficient value reaching the order of 105/cm, even much larger in the ultraviolet, suggesting the promising optoelectronic applicability. Finally, the thermoelectric parameters including electrical conductivity, thermal conductivity, Seebeck coefficient, power factor and figure of merit are determined and analyzed. Results indicate prospective thermoelectric performance of both considered single layers as demonstrated by large figure of merit close to unity. Our work introduces two new 2D multifunctional materials that may possess potential applications in the optoelectronic and thermoelectric nano-devices.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 2.221
DOI: 10.1016/J.PHYSE.2021.114732
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“Classical molecules in two dimensions”. Peeters FM, Partoens B, Schweigert VA, Goldoni G, Physica: E 1, 219 (1997). http://doi.org/10.1016/S1386-9477(97)00069-6
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 5
DOI: 10.1016/S1386-9477(97)00069-6
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“Type of phase transitions in a mesoscopic superconducting disc”. Deo PS, Schweigert VA, Peeters FM, Geim AK, Physica: E 1, 297 (1997). http://doi.org/10.1016/S1386-9477(97)00063-5
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
DOI: 10.1016/S1386-9477(97)00063-5
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“Effects of intersubband interaction on multisubband electron transport in single and double quantum wells”. Hai GQ, Studart N, Marques GE, Peeters FM, Koenraad PM, Physica. E: Low-dimensional systems and nanostructures 2, 222 (1998). http://doi.org/10.1016/S1386-9477(98)00048-4
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 3
DOI: 10.1016/S1386-9477(98)00048-4
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“Electrical transport through magnetic barriers”. Ibrahim IS, Schweigert VA, Peeters FM, Physica. E: Low-dimensional systems and nanostructures 2, 899 (1998). http://doi.org/10.1016/S1386-9477(98)00183-0
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
DOI: 10.1016/S1386-9477(98)00183-0
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“Mini-gaps and novel giant negative magnetoresistance in InAs/GaSb semimetallic superlattice”. Lakrimi M, Khym S, Symons DM, Nicholas RJ, Peeters FM, Mason NJ, Walker PJ, Physica. E: Low-dimensional systems and nanostructures 2, 363 (1998). http://doi.org/10.1016/S1386-9477(98)00076-9
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 1
DOI: 10.1016/S1386-9477(98)00076-9
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“Resonant magnetopolaron effect in GaAs/AlGaAs multiple quantum well structures”. Wang YJ, Nichel HA, McCombe BD, Peeters FM, Shi JM, Hai GQ, Wu XG, Eustis TJ, Schaff W, Physica. E: Low-dimensional systems and nanostructures 2, 161 (1998). http://doi.org/10.1016/S1386-9477(98)00035-6
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
DOI: 10.1016/S1386-9477(98)00035-6
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“Theory of the band mixing induced negative magnetoresistance in broken gap superlattices”. Symons DM, Peeters FM, Lakrimi M, Khym S, Portal JC, Mason NJ, Nicholas RJ, Walker PJ, Physica. E: Low-dimensional systems and nanostructures 2, 353 (1998). http://doi.org/10.1016/S1386-9477(98)00074-5
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 4
DOI: 10.1016/S1386-9477(98)00074-5
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“The Hall resistivity of a two-dimensional electron gas in the presence of magnetic clusters with perpendicular magnetization”. Reijniers J, Peeters FM, Matulis A, Physica. E: Low-dimensional systems and nanostructures 6, 759 (2000). http://doi.org/10.1016/S1386-9477(99)00197-6
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Engineering Management (ENM)
Impact Factor: 2.221
Times cited: 9
DOI: 10.1016/S1386-9477(99)00197-6
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“Interminiband spectroscopy of biased superlattices”. Helm M, Hilber W, Strasser G, de Meester R, Peeters FM, Wacker A, Physica. E: Low-dimensional systems and nanostructures 7, 274 (2000). http://doi.org/10.1016/S1386-9477(99)00275-1
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 1
DOI: 10.1016/S1386-9477(99)00275-1
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“Intersubband transitions in InAs/GaSb superlattices in a parallel magnetic field”. de Meester RHJ, Peeters FM, Lakrimi M, Nicholas RJ, Poulter AJL, Mason NJ, Walker PJ, Physica. E: Low-dimensional systems and nanostructures 7, 93 (2000)
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 1
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“The spin structure of two vertically coupled quantum dots”. Partoens B, Peeters FM, Physica. E: Low-dimensional systems and nanostructures 6, 577 (2000). http://doi.org/10.1016/S1386-9477(99)00114-9
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 2
DOI: 10.1016/S1386-9477(99)00114-9
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“Strong resonant intersubband magnetopolaron effect in heavily modulation-doped GaAs/AlGaAs single quantum wells at high magnetic fields”. Wang YJ, Leem YA, McCombe BD, Wu XG, Peeters FM, Jones E, Reno J, Lee XY, Jiang HW, Physica. E: Low-dimensional systems and nanostructures 6, 195 (2000). http://doi.org/10.1016/S1386-9477(99)00086-7
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 2
DOI: 10.1016/S1386-9477(99)00086-7
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“Transition from two-dimensional to three-dimensional classical artificial atoms”. Cornelissens YG, Partoens B, Peeters FM, Physica. E: Low-dimensional systems and nanostructures 8, 314 (2000). http://doi.org/10.1016/S1386-9477(00)00163-6
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 16
DOI: 10.1016/S1386-9477(00)00163-6
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“Confined states in two-dimensional flat elliptic quantum dots and elliptic quantum wires”. van den Broek M, Peeters FM, Physica. E: Low-dimensional systems and nanostructures 11, 345 (2001). http://doi.org/10.1016/S1386-9477(01)00169-2
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 54
DOI: 10.1016/S1386-9477(01)00169-2
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“Electron and hole localization in coupled InP/InGaP self-assembled quantum dots”. Tadić, M, Peeters FM, Partoens B, Janssens KL, Physica. E: Low-dimensional systems and nanostructures 13, 237 (2002). http://doi.org/10.1016/S1386-9477(01)00528-8
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 5
DOI: 10.1016/S1386-9477(01)00528-8
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“Electronic structure of the valence band in cylindrical strained InP/InGaP quantum dots in an external magnetic field”. Tadic, Peeters FM, Physica. E: Low-dimensional systems and nanostructures
T2 –, 14th International Conference on the Electronic Properties of, Two-Dimensional Systems, July 30-August 03, 2001, Prague, Czech Republic 12, 880 (2002). http://doi.org/10.1016/S1386-9477(01)00445-3
Abstract: The multiband effective-mass model of cylindrical self-assembled quantum dots in a magnetic field normal to the layer of the quantum dots is presented. The strain distribution is computed by the valence force field method. The strain-dependent multiband Hamiltonian is modified into an axially symmetric form, which commutes with the total angular momentum F-2 = fh. where f denotes the total magnetic quantum number. The heavy hole and the light hole parts in the mixed hole state are resolved. It is found that the heavy hole component dominates in the ground states for both f = 1/2 and 3/2. The electronic structure exhibits numerous anticrossings between the hole levels. The Zeeman splitting between the +\f\ and -\f\ states is also computed. (C) 2002 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 1
DOI: 10.1016/S1386-9477(01)00445-3
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“Magnetic confinement of electrons into quantum wires and dots on a liquid helium surface”. Freire JAK, Studart N, Peeters FM, Farias GA, Freire VN, Physica. E: Low-dimensional systems and nanostructures
T2 –, 14th International Conference on the Electronic Properties of, Two-Dimensional Systems, July 30-August 03, 2001, Prague, Czech Republic 12, 946 (2002). http://doi.org/10.1016/S1386-9477(01)00416-7
Abstract: We investigate the possibility to laterally confine surface electrons on a liquid helium surface by inserting magnetic discs and stripes which generate nonhomogeneous magnetic field profiles. (C) 2002 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 2
DOI: 10.1016/S1386-9477(01)00416-7
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“Quenching of the Hall effect in localised high magnetic field regions”. Novoselov KS, Geim AK, Dubonos SV, Cornelissens YG, Peeters FM, Maan JC, Physica. E: Low-dimensional systems and nanostructures 12, 244 (2002). http://doi.org/10.1016/S1386-9477(01)00364-2
Abstract: We report the suppression of the Hall effect in a mesoscopic Hall cross with a strong magnetic field only in the centre and vanishingly small outside, The local magnetic field is produced by placing Dy pillar on top of a structure with a high-mobility two-dimensional electron gas. The effect is found to be due to a sharp increase of the number of back-scattered and quasi-localised electron orbits. The possibility of localising electrons inside the magnetic inhomogeneity region is discussed. (C) 2002 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 3
DOI: 10.1016/S1386-9477(01)00364-2
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“Spin-engineered quantum dots”. Fleurov V, Ivanov VA, Peeters FM, Vagner ID, Physica. E: Low-dimensional systems and nanostructures 14, 361 (2002). http://doi.org/10.1016/S1386-9477(01)00487-8
Abstract: Spatially nonhomogeneously spin polarized nuclei are proposed as a new mechanism to monitor electron states in a nanostructure, or as a means to create and, if necessary, reshape such nanostructures in the course of the experiment. We found that a polarization of nuclear spins may lift the spin polarization of the electron states in a nanostructure and, if sufficiently strong, leads to a polarization of the electron spins. Polarized nuclear spins may form an energy landscape capable of binding electrons with energy up to several meV and the localization radius > 100 Angstrom. (C) 2002 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 12
DOI: 10.1016/S1386-9477(01)00487-8
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“Theory of trions in quantum wells”. Riva C, Peeters FM, Varga K, Physica. E: Low-dimensional systems and nanostructures
T2 –, 14th International Conference on the Electronic Properties of, Two-Dimensional Systems, JUL 30-AUG 03, 2001, PRAGUE, CZECH REPUBLIC 12, 543 (2002). http://doi.org/10.1016/S1386-9477(01)00484-2
Abstract: We investigate the energy levels of the negatively and positively charged excitons (also called trions) in a 200 Angstrom wide GaAs quantum well in the presence of a perpendicular magnetic field. A comparison is made with the experimental results of Glasberg et al. (Phys. Rev. B. 59 (1999) R10 425) and of Yusa et al. (cond-mat/0103505). (C) 2002 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 2
DOI: 10.1016/S1386-9477(01)00484-2
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“Vortex states in mescopic superconductors”. Peeters FM, Baelus BJ, Milošević, MV, Physica. E: Low-dimensional systems and nanostructures 18, 312 (2003). http://doi.org/10.1016/S1386-9477(02)01058-5
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 1
DOI: 10.1016/S1386-9477(02)01058-5
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“Electroluminescence spectra of an STM-tip-induced quantum dot”. Croitoru MD, Gladilin VN, Fomin VM, Devreese JT, Kemerink M, Koenraad PM, Sauthoff K, Wolter JH, Physica. E: Low-dimensional systems and nanostructures 21, 270 (2004). http://doi.org/10.1016/j.physe.2003.11.028
Keywords: A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT)
Impact Factor: 2.221
Times cited: 1
DOI: 10.1016/j.physe.2003.11.028
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“Influence of strain on the magneto-exciton in single and coupled InP/GaInP quantum disks”. Janssens KL, Partoens B, Peeters FM, Physica. E: Low-dimensional systems and nanostructures 21, 349 (2004). http://doi.org/10.1016/j.physe.2003.11.269
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
DOI: 10.1016/j.physe.2003.11.269
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