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Author Barbier, M.; Papp, G.; Peeters, F.M.
Title Snake states and Klein tunneling in a graphene Hall bar with a pn-junction Type A1 Journal article
Year 2012 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 100 Issue 16 Pages 163121-163121,3
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The Hall (R-H) and bend (R-B) resistances of a graphene Hall bar structure containing a pn-junction are calculated when in the ballistic regime. The simulations are done using the billiard model. Introducing a pn-junction-dividing the Hall bar geometry in two regions-leads to two distinct regimes exhibiting very different physics: (1) both regions are of n-type and (2) one region is n-type and the other p-type. In regime (1), a “Hall plateau”-an enhancement of the resistance-appears for R-H. On the other hand, in regime (2), we found a negative R-H, which approaches zero for large B. The bend resistance is highly asymmetric in regime (2) and the resistance increases with increasing magnetic field B in one direction while it reduces to zero in the other direction. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4704667]
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000303128500064 Publication Date 2012-04-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 20 Open Access
Notes ; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-EuroGRAPHENE project CONGRAN. ; Approved Most recent IF: 3.411; 2012 IF: 3.794
Call Number UA @ lucian @ c:irua:99129 Serial 3047
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Author Arsoski, V.; Čukarić, N.; Tadić, M.; Peeters, F.M.
Title Exciton states in a nanocup in the presence of a perpendicular magnetic field Type A1 Journal article
Year 2012 Publication Physica scripta Abbreviated Journal Phys Scripta
Volume T149 Issue Pages 014054-014054,5
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The exciton states in a strained (In,Ga)As/GaAs nanocup are theoretically determined. We explore how the nanocup bottom thickness (t) affects the magnetic field dependence of the exciton energy. Strain distribution is computed by the continuum mechanical model under the approximation of isotropic elasticity. The exciton wave functions are expanded into products of the electron and hole envelope functions. For small t, the exciton ground state has zero orbital momentum and exhibits small oscillations of the second derivative when the magnetic field increases. When t approaches the value of the cup height, however, the exciton levels exhibit angular momentum transitions, whose behavior is similar to that for type-II quantum dots. Small oscillations of the oscillator strength for exciton recombination are found when the magnetic field increases. An increase in thickness of the nanocup bottom has only a small effect on those oscillations for the optically active exciton states, but the exciton ground state becomes dark when the magnetic field increases. Hence, the results of our calculations show that an increase in thickness of the nanocup bottom transforms the exciton ground energy level dependence on magnetic field from the one characteristic of type-I rings to the one characteristic of type-II dots.
Address
Corporate Author Thesis
Publisher Place of Publication Stockholm Editor
Language Wos 000303523500055 Publication Date 2012-04-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-8949;1402-4896; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 1.28 Times cited 2 Open Access
Notes ; This work was supported by the EU Network of Excellence SANDiE, the Ministry of Education and Science of Serbia, the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 1.28; 2012 IF: 1.032
Call Number UA @ lucian @ c:irua:99135 Serial 1117
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Author Grujić, M.; Zarenia, M.; Tadić, M.; Peeters, F.M.
Title Interband optical absorption in a circular graphene quantum dot Type A1 Journal article
Year 2012 Publication Physica scripta Abbreviated Journal Phys Scripta
Volume T149 Issue Pages 014056-014056,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate the energy levels and optical properties of a circular graphene quantum dot in the presence of an external magnetic field perpendicular to the dot. Based on the Dirac-Weyl equation and assuming zero outward current at the edge of the dot we present the results for two different types of boundary conditions, i.e. infinite-mass (IMBC) and zigzag boundary conditions. We found that the dot with zigzag edges displays a zero-energy state in the energy spectra while this is not the case for the IMBCs. For both boundary conditions, the confinement becomes dominated by the magnetic field, where the energy levels converge to the Landau levels as the magnetic field increases. The effect of boundary conditions on the electron-and hole-energy states is found to affect the interband absorption spectra, where we found larger absorption in the case of IMBCs. The selection rules for interband optical transitions are determined and discussed for both boundary conditions.
Address
Corporate Author Thesis
Publisher Place of Publication Stockholm Editor
Language Wos 000303523500057 Publication Date 2012-04-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-8949;1402-4896; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 1.28 Times cited 5 Open Access
Notes ; This work was supported by the EuroGraphene program of the ESF (project CONGRAN), the Ministry of Education and Science of Serbia, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 1.28; 2012 IF: 1.032
Call Number UA @ lucian @ c:irua:99136 Serial 1688
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Author Dong, H.M.; Xu, W.; Zhang, J.; Peeters, F.M.; Vasilopoulos, P.
Title Photo-excited carriers and optical conductance and transmission in graphene in the presence of phonon scattering Type A1 Journal article
Year 2010 Publication Physica. E: Low-dimensional systems and nanostructures Abbreviated Journal Physica E
Volume 42 Issue 4 Pages 748-750
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We present a theoretical study of the optoelectronic properties of monolayer graphene. Including the effect of the electron-photon-phonon scattering, we employ the mass- and energy-balance equations derived from the Boltzmann equation to evaluate self-consistently the carrier densities, optical conductance and transmission coefficient in graphene in the presence of linearly polarized radiation field. We find that the photo-excited carrier density can be increased under infrared radiation and depend strongly on radiation intensity and frequency. For short wavelengths (lambda <3 mu m), the universal optical conductance sigma(0) = e(2)/4h is obtained and the light transmittance is about 0.97-0.98. Interestingly, there is an optical absorption window in the range 4-100 mu m which is induced by different transition energies required for inter- and intra-band optical absorption. The position and width of this absorption window depend sensitively on temperature and carrier density of the system. These results are relevant for applications of recently developed graphene devices in advanced optoelectronics such as the infrared photodetectors. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher North-Holland Place of Publication Amsterdam Editor
Language Wos 000276541200022 Publication Date 2009-11-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1386-9477; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 2.221 Times cited 7 Open Access
Notes ; ; Approved Most recent IF: 2.221; 2010 IF: 1.304
Call Number UA @ lucian @ c:irua:99216 Serial 2607
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Author Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M.
Title Tuning the superconducting properties of nanomaterials Type H1 Book chapter
Year 2009 Publication Abbreviated Journal
Volume Issue Pages 1-14
Keywords H1 Book chapter; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT)
Abstract Electron continement and its effect on the superconducting-to-normal phase transition driven by a magentic field and/or a current is studied in nanowires. Our investigation is based on a self-consistent numerical solution of the Bogoliubov-de Gennes equations. We find that in a parallel magneitc field and/or in the presence of a supercurrent the transition from the superconducting to the normal phase occurs as a cascade of discontinuous jumps in the superconducting order parameter for diameters D < 10 divided by 15 nm at T = 0. The critical magentic field exhibits quantum-size oscillations with pronounced resonant enhancements as a function of the wire radius.
Address
Corporate Author Thesis
Publisher Springer Place of Publication Dordrecht Editor
Language Wos 000274282900001 Publication Date 2009-07-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1874-6500; ISBN 978-90-481-3118-1 Additional Links (up) UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:99226 Serial 3761
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Author Doria, M.M.; de Romaguera, A.R.C.; Milošević, M.V.; Peeters, F.M.
Title Domain coexistence of magnetism and superconductivity : appearance of confined vortex loops Type P1 Proceeding
Year 2008 Publication Journal of physics : conference series Abbreviated Journal
Volume 97 Issue Pages 012070-012070,4
Keywords P1 Proceeding; Condensed Matter Theory (CMT)
Abstract A magnetic moment inside an extreme type II superconductor can have three, but not one or two, confined vortex loops near to the core. For a sub-micron superconducting particle the confined vortex loops eventually break up and reach the surface turning into external vortex pairs.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000276054100070 Publication Date 2008-03-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-6596; ISBN Additional Links (up) UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:99232 Serial 747
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Author Baelus, B.J.; Kanda, A.; Peeters, F.M.; Ootuka, Y.; Kadowaki, K.
Title Giant and multivortex states in mesoscopic superconducting disks Type A1 Journal article
Year 2005 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 426 Issue 1 Pages 132-135
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Transitions between different multivortex states and transitions between multivortex states and giant vortex states are observed in mesoscopic superconducting disks using the multiple-small-tunnel-junction method. These results are compared to theoretical calculations within the framework of the nonlinear Ginzburg-Landau theory. We find a good qualitative agreement between the theoretical and experimental results, when we assume that a small defect is present near the center of the experimental sample. (c) 2005 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000232698500029 Publication Date 2005-06-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534; ISBN Additional Links (up) UA library record; WoS full record
Impact Factor 1.404 Times cited Open Access
Notes Approved Most recent IF: 1.404; 2005 IF: 0.948
Call Number UA @ lucian @ c:irua:99281 Serial 1336
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Author Papp, G.; Peeters, F.M.
Title Magneto conductance for tunnelling through double magnetic barriers Type A1 Journal article
Year 2005 Publication Physica. E: Low-dimensional systems and nanostructures Abbreviated Journal Physica E
Volume 25 Issue 4 Pages 339-346
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The temperature-dependent magnetoresistance effect is investigated in a magnetically modulated two-dimensional (21)) electron gas (2DEG) which can be realized by depositing two parallel ferromagnets on top of a 2DEG electron gas. In the resonant tunnelling regime the transmission for the parallel and antiparallel magnetization configurations shows a quite distinct dependence on the longitudinal wave vector of the incident electrons. This leads to a very large magneto resistance ratio with a strong temperature dependence. (C) 2004 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher North-Holland Place of Publication Amsterdam Editor
Language Wos 000226187900002 Publication Date 2004-09-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1386-9477; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 2.221 Times cited 25 Open Access
Notes Approved Most recent IF: 2.221; 2005 IF: 0.946
Call Number UA @ lucian @ c:irua:99308 Serial 1898
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Author Tadić, M.; Peeters, F.M.
Title Exciton states and oscillator strength in two vertically coupled InP/InGaP quantum discs Type A1 Journal article
Year 2004 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 16 Issue 47 Pages 8633-8652
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Quantum mechanical coupling and strain in two vertically arranged InP/InGaP quantum dots is studied as a function of the size of the dots and the spacer thickness. The strain distribution is determined by the continuum mechanical model, while the single-band effective-mass equation and the multiband k (.) p theory are employed to compute the conduction and valence band energy levels, respectively. The exciton states are obtained from an exact diagonalization approach, and we also compute the oscillator strength for recombination. We found that the light holes are confined by strain to the spacer, which is the reason that the hole states exhibit coupling at much larger distances as compared with the electrons. At small d, the doublet structure of the hole energy levels arises as a consequence of the relocation of the light hole from the matrix to the regions located-outside the stack, close to the dot-matrix interface. When d varies, the exciton ground state exhibits numerous anticrossings with other states, which are related to the changing spatial localization of the hole as a function of d. The oscillator strength of the exciton recombination is strongly reduced in a certain range of spacer thicknesses, which effectively turns a bright exciton state into a dark one. This effect is associated with anticrossings between exciton energy levels.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000225796800016 Publication Date 2004-11-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 13 Open Access
Notes Approved Most recent IF: 2.649; 2004 IF: 2.049
Call Number UA @ lucian @ c:irua:99315 Serial 1116
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Author Anisimovas, E.; Peeters, F.M.
Title Dynamic response of artificial bipolar molecules Type A1 Journal article
Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 66 Issue 7 Pages 075311
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We calculate the equilibrium properties and the dynamic response of two vertically coupled circular quantum dots populated by particles of different electrical charge sign, i.e., electrons and holes. The equilibrium density profiles are obtained and used to compute the frequencies and oscillator strengths of magnetoplasma excitations. We find a strong coupling between the modes derived from the center-of-mass modes of the individual dots which leads to an anticrossing with a pronounced oscillator strength transfer from the “acoustic” to the “optical” branch. Also, due to the breaking of the generalized Kohn theorem a number of other than center-of-mass modes are excited whose oscillator strengths, however, are rather weak.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000177969800103 Publication Date 2002-10-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 9 Open Access
Notes Approved Most recent IF: 3.836; 2002 IF: NA
Call Number UA @ lucian @ c:irua:99397 Serial 765
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Author Peeters, F.M.; Schweigert, V.A.; Baelus, B.J.
Title Fractional and negative flux penetration in mesoscopic superconducting disks Type A1 Journal article
Year 2002 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 369 Issue 1-4 Pages 158-164
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The one vortex entry in a superconducting disk is investigated within the non-linear Ginzburg-Landau theory near the first critical field. We find that in mesoscopic superconducting disks the magnetic flux enters with fractions of one flux quantum phi(0) = ch/2e. For disks with a very smooth surface it is possible to drive the Meissner state so far into the metastable region that at the vortex entry a net amount of flux is expelled from the superconductor. We show that the magnetic field for flux entry is very sensitive to indentations of the disk surface and only weakly to bulges. On the other hand the flux exit field is practically insensitive to such geometrical surface defects. Our results are in agreement with recent experimental findings. (C) 2001 Elsevier Science B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000174200000023 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 1.404 Times cited 11 Open Access
Notes Approved Most recent IF: 1.404; 2002 IF: 0.912
Call Number UA @ lucian @ c:irua:99412 Serial 1272
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Author Riva, C.; Peeters, F.M.; Varga, K.; Schweigert, V.A.
Title Correlation energy and configuration of biexcitons in quantum wells Type A1 Journal article
Year 2002 Publication Physica status solidi: B: basic research Abbreviated Journal Phys Status Solidi B
Volume 234 Issue 1 Pages 50-57
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A calculation of the energy of a biexciton in a GaAs/AlGaAs quantum wen is presented. We compare the results obtained using two different techniques. We discuss the dependence of the biexciton correlation energy and binding energy on the electron/hole mass ratio and on the well width. The structure of the biexciton is also investigated.
Address
Corporate Author Thesis
Publisher Place of Publication Berlin Editor
Language Wos 000179600900009 Publication Date 2002-11-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-1972;1521-3951; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 1.674 Times cited 6 Open Access
Notes Approved Most recent IF: 1.674; 2002 IF: 0.930
Call Number UA @ lucian @ c:irua:99604 Serial 526
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Author Hilber, W.; Helm, M.; Peeters, F.M.; Alavi, K.; Pathak, R.N.
Title Impurity band and magnetic-field-induced metal-insulator transition in a doped GaAs/AlxGa1-xAs superlattice Type A1 Journal article
Year 1996 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 53 Issue 11 Pages 6919-6922
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A combination of infrared spectroscopy and magnetotransport is used to investigate the impurity band and the magnetic-field-induced metal-insulator transition in n-type GaAs/AlxGa1-xAs superlattices. The dropping of the Fermi level from the conduction band into the impurity band upon increasing magnetic field is observed in a sample doped to n=4n(c), where n(c) is the critical density according to the Mott criterion. The metal-insulator transition takes place while the Fermi level is in the impurity band, with no qualitative change from the metallic to the insulating side. Due to the anisotropy of the superlattice band structure, the metal-insulator transition is shifted to higher magnetic field, when the magnetic field is tilted away from the growth axis towards the layer planes.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos A1996UC74000018 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 3.736 Times cited 14 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:99676 Serial 1571
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Author van der Burgt, M.; Karavolas, V.C.; Peeters, F.M.; Singleton, J.; Nicholas, R.J.; Herlach, F.; Harris, J.J.; Van Hove, M.; Borghs, G.
Title Magnetotransport in a pseudomorphic GaAs/Ga0.8In0.2As/Ga0.75Al0.25As heterostructure with a Si \delta-doping layer Type A1 Journal article
Year 1995 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 52 Issue 16 Pages 12218-12231
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Magnetotransport properties of a pseudomorphic GsAs/Ga0.8In0.2As/Ga0.75Al0.25As heterostructure are investigated in pulsed magnetic fields up to 50 T and at temperatures of T = 1.4 and 4.2 K. The structure studied consists of a Si delta layer parallel to a Ga0.8In0.2As quantum well (QW). The dark electron density of the structure is n(c) = 1.67 x 10(16) m(-2). By illumination the density can be increased up to a factor of 4; this way the second subband in the Ga0.08In0.2As QW can become populated as well as the Si delta layer. The presence of electrons in the delta layer results in drastic changes in the transport data, especially at magnetic fields beyond 30 T. The phenomena observed are interpreted as (i) magnetic freeze-out of carriers in the delta layer when a low density of electrons is present in the delta layer, and (ii) quantization of the electron motion in the two-dimensional electron gases in both the Ga0.8In0.2As QW and the Si delta layer in the case of high densities. These conclusions are corroborated by the numerical results of our theoretical model. We obtain satisfactory agreement between model and experiment.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1995TB96600102 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 3.736 Times cited 43 Open Access
Notes Approved PHYSICS, APPLIED 28/145 Q1 #
Call Number UA @ lucian @ c:irua:99708 Serial 1933
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Author Shi, J.M.; Peeters, F.M.; Devreese, J.T.
Title Shallow donor impurities in GaAs/AlxGa1-xAs superlattices in a magnetic-field Type A1 Journal article
Year 1994 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 50 Issue 20 Pages 15182-15190
Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos A1994PV86500054 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 3.736 Times cited 71 Open Access
Notes Approved MATERIALS SCIENCE, MULTIDISCIPLINARY 96/271 Q2 #
Call Number UA @ lucian @ c:irua:99812 Serial 2986
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Author Nicholas, R.J.; Sasaki, S.; Miura, N.; Peeters, F.M.; Shi, J.M.; Hai, G.Q.; Devreese, J.T.; Lawless, M.J.; Ashenford, D.E.; Lunn, B.
Title Interband magnetooptical studies of resonant polaron coupling in CdTe/Cd1-xMnxTe quantum-wells Type A1 Journal article
Year 1994 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 50 Issue 11 Pages 7596-7601
Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Abstract Magnetoreflectivity measurements of the 1s and 2s exciton energies in a CdTe/Cd1-xMnxTe superlattice have been made in magnetic fields up to 45 T, showing the resonant polaron coupling of electrons to LO phonons. Strong reflectivity features are seen for both the 1s and 2s excitons, which show a strong field-dependent spin splitting due to the dilute magnetic barriers. At B-z=0, the 2s exciton feature is observed lying 18 meV above the Is state, and is shifted upward in energy by the magnetic fields. No resonant behavior occurs when the 2s state passes through the LO-phonon energy of 21 meV, but at higher fields of around 20 T, the resonances for both spin states (sigma(+/-)) of the 2s exciton broaden and show a strong anticrossing behavior. These experiments are shown to be in excellent agreement with a theoretical treatment which includes the resonant polaron coupling of the electrons alone. Both experiment and theory demonstrate an extremely strong resonant splitting of the 2s exciton states of approximately 11 meV, which is over 50% of the LO-phonon energy. The dominance of single-particle polaron coupling is attributed to the relative sizes of the polaron (35 Angstrom A) and the exciton (50 Angstrom A) radius.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos A1994PJ43700045 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 3.736 Times cited 10 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:99837 Serial 1687
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Author Schweigert, V.A.; Peeters, F.M.
Title Dynamics of a finite classical two-dimensional system Type A1 Journal article
Year 1994 Publication Superlattices and microstructures Abbreviated Journal Superlattice Microst
Volume 16 Issue 3 Pages 243-247
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The spectral properties of a classical two-dimensional (2D) cluster of charged particles which are confined by a quadratic potential are calculated. Using the method of Newton optimization we obtain the ground state and the metastable states. For a given configuration the eigenvectors and eigenfrequencies for the normal modes are obtained using the Householder diagonalization technique for the dynamical matrix whose elements are the second derivative of the potential energy. For small clusters the lowest excitation corresponds to an intershell rotation. Magic numbers are associated to clusters which are most stable against intershell rotation. For large clusters the lowest excitation is a vortex/anti-vortex pair.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos A1994QE75400007 Publication Date 2009-07-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0749-6036; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
Impact Factor 2.097 Times cited 4 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:99951 Serial 772
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