Records |
Author |
Topalovic, D.B.; Arsoski, V.V.; Pavlovic, S.; Cukaric, N.A.; Tadic, M.Z.; Peeters, F.M. |
Title |
On improving accuracy of finite-element solutions of the effective-mass Schrodinger equation for interdiffused quantum wells and quantum wires |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Communications in theoretical physics |
Abbreviated Journal |
Commun Theor Phys |
Volume |
65 |
Issue |
1 |
Pages |
105-113 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We use the Galerkin approach and the finite-element method to numerically solve the effective-mass Schrodinger equation. The accuracy of the solution is explored as it varies with the range of the numerical domain. The model potentials are those of interdiffused semiconductor quantum wells and axially symmetric quantum wires. Also, the model of a linear harmonic oscillator is considered for comparison reasons. It is demonstrated that the absolute error of the electron ground state energy level exhibits a minimum at a certain domain range, which is thus considered to be optimal. This range is found to depend on the number of mesh nodes N approximately as alpha(0) log(e)(alpha 1) (alpha N-2), where the values of the constants alpha(0), alpha(1), and alpha(2) are determined by fitting the numerical data. And the optimal range is found to be a weak function of the diffusion length. Moreover, it was demonstrated that a domain range adaptation to the optimal value leads to substantial improvement of accuracy of the solution of the Schrodinger equation. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Wallingford |
Editor |
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Language |
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Wos |
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Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0253-6102; 1572-9494 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
0.989 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 0.989 |
Call Number |
UA @ lucian @ c:irua:133213 |
Serial |
4216 |
Permanent link to this record |
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Author |
Cukaric, N.A.; Partoens, B.; Tadic, M.Z.; Arsoski, V.V.; Peeters, F.M. |
Title |
The 30-band k . p theory of valley splitting in silicon thin layers |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
28 |
Issue |
28 |
Pages |
195303 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The valley splitting of the conduction-band states in a thin silicon-on-insulator layer is investigated using the 30-band k . p theory. The system composed of a few nm thick Si layer embedded within thick SiO2 layers is analyzed. The valley split states are found to cross periodically with increasing quantum well width, and therefore the energy splitting is an oscillatory function of the quantum well width, with period determined by the wave vector K-0 of the conduction band minimum. Because the valley split states are classified by parity, the optical transition between the ground hole state and one of those valley split conduction band states is forbidden. The oscillations in the valley splitting energy decrease with electric field and with smoothing of the composition profile between the well and the barrier by diffusion of oxygen from the SiO2 layers to the Si quantum well. Such a smoothing also leads to a decrease of the interband transition matrix elements. The obtained results are well parametrized by the effective two-valley model, but are found to disagree from previous 30-band calculations. This discrepancy could be traced back to the fact that the basis for the numerical solution of the eigenproblem must be restricted to the first Brillouin zone in order to obtain quantitatively correct results for the valley splitting. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000374394700009 |
Publication Date |
2016-04-19 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0953-8984 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
2.649 |
Times cited |
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Open Access |
|
Notes |
; This work was supported by the Ministry of Education, Science, and Technological Development of Serbia, the Flemish fund for Scientific Research (FWO-Vl), and the Methusalem programme of the Flemish government. ; |
Approved |
Most recent IF: 2.649 |
Call Number |
UA @ lucian @ c:irua:133610 |
Serial |
4261 |
Permanent link to this record |
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Author |
Jakovljevic, D.Z.; Grujic, M.M.; Tadic, M.Z.; Peeters, F.M. |
Title |
Helical edge states in silicene and germanene nanorings in perpendicular magnetic field |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
30 |
Issue |
3 |
Pages |
035301 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
<script type='text/javascript'>document.write(unpmarked('Due to nonzero intrinsic spin-orbit interaction in buckled honeycomb crystal structures, silicene and germanene exhibit interesting topological properties, and are therefore candidates for the realization of the quantum spin Hall effect. We employ the Kane-Mele model to investigate the electron states in hexagonal silicene and germanene nanorings having either zigzag or armchair edges in the presence of a perpendicular magnetic field. We present results for the energy spectra as function of magnetic field, the electron density of the spin-up and spin-down states in the ring plane, and the calculation of the probability current density. The quantum spin Hall phase is found at the edges between the nontrivial topological phase in silicene and germanene and vacuum. We demonstrate that the helical edge states in zigzag silicene and germanene nanorings can be qualitatively well understood by means of classical magnetic moments. However, this is not the case for comparable-sized armchair nanorings, where the eigenfunctions spread throughout the ring. Finally, we note that the energy spectra of silicene and germanene nanorings are similar and that the differences between the two are mainly related to the difference in magnitude of the spin-orbit coupling.')); |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000418354400001 |
Publication Date |
2017-11-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0953-8984 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
2.649 |
Times cited |
4 |
Open Access |
|
Notes |
; This work was supported by Erasmus+ and the Serbian Ministry of Education, Science and Technological Development (Project No. III45003). ; |
Approved |
Most recent IF: 2.649 |
Call Number |
UA @ lucian @ c:irua:148426UA @ admin @ c:irua:148426 |
Serial |
4878 |
Permanent link to this record |
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Author |
Topalovic, D.B.; Arsoski, V.V.; Tadic, M.Z.; Peeters, F.M. |
Title |
Asymmetric versus symmetric HgTe/CdxHg1-x Te double quantum wells: Bandgap tuning without electric field |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Journal Of Applied Physics |
Abbreviated Journal |
J Appl Phys |
Volume |
128 |
Issue |
6 |
Pages |
064301-64308 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate the electron states in double asymmetric HgTe / Cd x Hg 1 – x Te quantum wells grown along the [ 001 ] direction. The subbands are computed by means of the envelope function approximation applied to the eight-band Kane k . mml:mspace width=“.1em”mml:mspace p model. The asymmetry of the confining potential of the double quantum wells results in a gap opening, which is absent in the symmetric system where it can only be induced by an applied electric field. The bandgap and the subbands are affected by spin-orbit coupling, which is a consequence of the asymmetry of the confining potential. The electron-like and hole-like states are mainly confined in different quantum wells, and the enhanced hybridization between them opens a spin-dependent hybridization gap at a finite in-plane wavevector. We show that both the ratio of the widths of the two quantum wells and the mole fraction of the C d x H g 1 – x Te barrier control both the energy gap between the hole-like states and the hybridization gap. The energy subbands are shown to exhibit inverted ordering, and therefore, a nontrivial topological phase could emerge in the system. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000561339300001 |
Publication Date |
2020-08-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; 1089-7550 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
3.2 |
Times cited |
4 |
Open Access |
|
Notes |
; This research was funded by the Ministry of Education, Science and Technological Development of the Republic of Serbia and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.2; 2020 IF: 2.068 |
Call Number |
UA @ admin @ c:irua:171146 |
Serial |
6453 |
Permanent link to this record |
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Author |
Milovanović, S.P.; Tadic, M.Z.; Peeters, F.M. |
Title |
Graphene membrane as a pressure gauge |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
111 |
Issue |
4 |
Pages |
043101 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Straining graphene results in the appearance of a pseudo-magnetic field which alters its local electronic properties. Applying a pressure difference between the two sides of the membrane causes it to bend/bulge resulting in a resistance change. We find that the resistance changes linearly with pressure for bubbles of small radius while the response becomes non-linear for bubbles that stretch almost to the edges of the sample. This is explained as due to the strong interference of propagating electronic modes inside the bubble. Our calculations show that high gauge factors can be obtained in this way which makes graphene a good candidate for pressure sensing. Published by AIP Publishing. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000406779700035 |
Publication Date |
2017-07-24 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-6951; 1077-3118 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
3.411 |
Times cited |
11 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem program, the Erasmus+ programme, and the Serbian Ministry of Education, Science and Technological Development. ; |
Approved |
Most recent IF: 3.411 |
Call Number |
UA @ lucian @ c:irua:145202 |
Serial |
4718 |
Permanent link to this record |
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Author |
Grujić, M.M.; Tadic, M.Z.; Peeters, F.M. |
Title |
Chiral properties of topological-state loops |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
91 |
Issue |
91 |
Pages |
245432 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The angular momentum quantization of chiral gapless modes confined to a circularly shaped interface between two different topological phases is investigated. By examining several different setups, we show analytically that the angular momentum of the topological modes exhibits a highly chiral behavior, and can be coupled to spin and/or valley degrees of freedom, reflecting the nature of the interface states. A simple general one-dimensional model, valid for arbitrarily shaped loops, is shown to predict the corresponding energies and the magnetic moments. These loops can be viewed as building blocks for artificial magnets with tunable and highly diverse properties. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000356928200005 |
Publication Date |
2015-06-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
3.836 |
Times cited |
6 |
Open Access |
|
Notes |
; This work was supported by the Ministry of Education, Science and Technological Development (Serbia), and the Fonds Wetenschappelijk Onderzoek (Belgium). ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
c:irua:127039 |
Serial |
357 |
Permanent link to this record |
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Author |
Grujić, M.M.; Ezawa, M.; Tadic, M.Z.; Peeters, F.M. |
Title |
Tunable skewed edges in puckered structures |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
245413 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We propose a type of edges arising due to the anisotropy inherent in the puckered structure of a honeycomb system such as in phosphorene. Skewed-zigzag and skewed-armchair nanoribbons are semiconducting and metallic, respectively, in contrast to their normal edge counterparts. Their band structures are tunable, and a metal-insulator transition is induced by an electric field. We predict a field-effect transistor based on the edge states in skewed-armchair nanoribbons, where the edge state is gapped by applying arbitrary small electric field E-z. A topological argument is presented, revealing the condition for the emergence of such edge states. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000377802700010 |
Publication Date |
2016-06-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
3.836 |
Times cited |
29 |
Open Access |
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Notes |
; This work was supported by the Serbian Ministry of Education, Science and Technological Development, and the Flemish Science Foundation (FWO-Vl). M.E. is thankful for the support by the Grants-in-Aid for Scientific Research from MEXT KAKENHI (Grants No. 25400317 and No. 15H05854). ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:134599 |
Serial |
4268 |
Permanent link to this record |
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Author |
Arsoski, V.V.; Grujić, M.M.; Čukarić, N.A.; Tadic, M.Z.; Peeters, F.M. |
Title |
Normal and skewed phosphorene nanoribbons in combined magnetic and electric fields |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
96 |
Issue |
12 |
Pages |
125434 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The energy spectrum and eigenstates of single-layer black phosphorus nanoribbons in the presence of a perpendicular magnetic field and an in-plane transverse electric field are investigated by means of a tight-binding method, and the effect of different types of edges is examined analytically. A description based on a continuum model is proposed using an expansion of the tight-binding model in the long-wavelength limit. Thewave functions corresponding to the flatband part of the spectrum are obtained analytically and are shown to agree well with the numerical results from the tight-binding method for both narrow (10 nm) and wide (100 nm) nanoribbons. Analytical expressions for the critical magnetic field at which Landau levels are formed and the ranges of wave numbers in the dispersionless flatband segments in the energy spectra are derived. We examine the evolution of the Landau levels when an in-plane lateral electric field is applied, and we determine analytically how the edge states shift withmagnetic field. For wider nanoribbons, the conductance is shown to have a characteristic staircase shape in combined magnetic and electric fields. Some of the stairs in zigzag and skewed armchair nanoribbons originate from edge states that are found in the band gap. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
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Language |
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Wos |
000411572400008 |
Publication Date |
2017-09-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
3.836 |
Times cited |
8 |
Open Access |
|
Notes |
; This work was supported by Erasmus+, the Serbian Ministry of Education, Science and Technological Development, and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:146738 |
Serial |
4791 |
Permanent link to this record |
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Author |
Topalovic, D.B.; Arsoski, V.V.; Tadic, M.Z.; Peeters, F.M. |
Title |
Confined electron states in two-dimensional HgTe in magnetic field : quantum dot versus quantum ring behavior |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
100 |
Issue |
12 |
Pages |
125304 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate the electron states and optical absorption in square- and hexagonal-shaped two-dimensional (2D) HgTe quantum dots and quantum rings in the presence of a perpendicular magnetic field. The electronic structure is modeled by means of the sp(3)d(5)s* tight-binding method within the nearest-neighbor approximation. Both bulklike and edge states appear in the energy spectrum. The bulklike states in quantum rings exhibit Aharonov-Bohm oscillations in magnetic field, whereas no such oscillations are found in quantum dots, which is ascribed to the different topology of the two systems. When magnetic field varies, all the edge states in square quantum dots appear as quasibands composed of almost fully flat levels, whereas some edge states in quantum rings are found to oscillate with magnetic field. However, the edge states in hexagonal quantum dots are localized like in rings. The absorption spectra of all the structures consist of numerous absorption lines, which substantially overlap even for small line broadening. The absorption lines in the infrared are found to originate from transitions between edge states. It is shown that the magnetic field can be used to efficiently tune the optical absorption of HgTe 2D quantum dot and quantum ring systems. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000486638400007 |
Publication Date |
2019-09-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
3.836 |
Times cited |
4 |
Open Access |
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Notes |
; This work was supported by Projects No. III 41028, No. III 42008, and No. III 45003 funded by the Serbian Ministry of Education, Science and Technological Development, and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ admin @ c:irua:162787 |
Serial |
5409 |
Permanent link to this record |
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Author |
Arsoski, V.V.; Čukarić, N.A.; Tadic, M.Z.; Peeters, F.M. |
Title |
An efficient finite-difference scheme for computation of electron states in free-standing and core-shell quantum wires |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Computer physics communications |
Abbreviated Journal |
Comput Phys Commun |
Volume |
197 |
Issue |
197 |
Pages |
17-26 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The electron states in axially symmetric quantum wires are computed by means of the effective-mass Schrodinger equation, which is written in cylindrical coordinates phi, rho, and z. We show that a direct discretization of the Schrodinger equation by central finite differences leads to a non-symmetric Hamiltonian matrix. Because diagonalization of such matrices is more complex it is advantageous to transform it in a symmetric form. This can be done by the Liouville-like transformation proposed by Rizea et al. (2008), which replaces the wave function psi(rho) with the function F(rho) = psi(rho)root rho and transforms the Hamiltonian accordingly. Even though a symmetric Hamiltonian matrix is produced by this procedure, the computed wave functions are found to be inaccurate near the origin, and the accuracy of the energy levels is not very high. In order to improve on this, we devised a finite-difference scheme which discretizes the Schrodinger equation in the first step, and then applies the Liouville-like transformation to the difference equation. Such a procedure gives a symmetric Hamiltonian matrix, resulting in an accuracy comparable to the one obtained with the finite element method. The superior efficiency of the new finite-difference scheme (FDM) is demonstrated for a few p-dependent one-dimensional potentials which are usually employed to model the electron states in free-standing and core shell quantum wires. The new scheme is compared with the other FDM schemes for solving the effective-mass Schrodinger equation, and is found to deliver energy levels with much smaller numerical error for all the analyzed potentials. It also gives more accurate results than the scheme of Rizea et al., except for the ground state of an infinite rectangular potential in freestanding quantum wires. Moreover, the PT symmetry is invoked to explain similarities and differences between the considered FDM schemes. (C) 2015 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000362919500003 |
Publication Date |
2015-08-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0010-4655 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
3.936 |
Times cited |
4 |
Open Access |
|
Notes |
; This work was supported by the Ministry of Education, Science, and Technological Development of Serbia (project III 45003) and the Fonds Wetenschappelijk Onderzoek (Belgium). ; |
Approved |
Most recent IF: 3.936; 2015 IF: 3.112 |
Call Number |
UA @ lucian @ c:irua:129412 |
Serial |
4139 |
Permanent link to this record |