TY  - JOUR
AU  - Topalović, Dušan
AU  - Arsoski, Vladimir V.
AU  - Tadić, Milan Ž.
AU  - Peeters, Francois M.
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9616
AB  - 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 ⋅ 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. © 2020 Author(s).
T2  - Journal of Applied Physics
T1  - Asymmetric versus symmetric HgTe / Cd x Hg 1 - X Te double quantum wells: Bandgap tuning without electric field
VL  - 128
IS  - 6
DO  - 10.1063/5.0016069
ER  - 

@article{
author = "Topalović, Dušan and Arsoski, Vladimir V. and Tadić, Milan Ž. and Peeters, Francois M.",
year = "2020",
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 ⋅ 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. © 2020 Author(s).",
journal = "Journal of Applied Physics",
title = "Asymmetric versus symmetric HgTe / Cd x Hg 1 - X Te double quantum wells: Bandgap tuning without electric field",
volume = "128",
number = "6",
doi = "10.1063/5.0016069"
}

Topalović, D., Arsoski, V. V., Tadić, M. Ž.,& Peeters, F. M.. (2020). Asymmetric versus symmetric HgTe / Cd x Hg 1 - X Te double quantum wells: Bandgap tuning without electric field. in Journal of Applied Physics, 128(6).
https://doi.org/10.1063/5.0016069

Topalović D, Arsoski VV, Tadić MŽ, Peeters FM. Asymmetric versus symmetric HgTe / Cd x Hg 1 - X Te double quantum wells: Bandgap tuning without electric field. in Journal of Applied Physics. 2020;128(6).
doi:10.1063/5.0016069 .

Topalović, Dušan, Arsoski, Vladimir V., Tadić, Milan Ž., Peeters, Francois M., "Asymmetric versus symmetric HgTe / Cd x Hg 1 - X Te double quantum wells: Bandgap tuning without electric field" in Journal of Applied Physics, 128, no. 6 (2020),
https://doi.org/10.1063/5.0016069 . .

TY  - JOUR
AU  - Topalović, Dušan
AU  - Arsoski, Vladimir
AU  - Tadić, Milan Ž.
AU  - Peeters, François M.
PY  - 2019
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8534
AB  - 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 sp3d5s∗ 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. © 2019 American Physical Society.
T2  - Physical Review B
T1  - Confined electron states in two-dimensional HgTe in magnetic field: Quantum dot versus quantum ring behavior
VL  - 100
IS  - 12
SP  - 125304
DO  - 10.1103/PhysRevB.100.125304
ER  - 

@article{
author = "Topalović, Dušan and Arsoski, Vladimir and Tadić, Milan Ž. and Peeters, François M.",
year = "2019",
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 sp3d5s∗ 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. © 2019 American Physical Society.",
journal = "Physical Review B",
title = "Confined electron states in two-dimensional HgTe in magnetic field: Quantum dot versus quantum ring behavior",
volume = "100",
number = "12",
pages = "125304",
doi = "10.1103/PhysRevB.100.125304"
}

Topalović, D., Arsoski, V., Tadić, M. Ž.,& Peeters, F. M.. (2019). Confined electron states in two-dimensional HgTe in magnetic field: Quantum dot versus quantum ring behavior. in Physical Review B, 100(12), 125304.
https://doi.org/10.1103/PhysRevB.100.125304

Topalović D, Arsoski V, Tadić MŽ, Peeters FM. Confined electron states in two-dimensional HgTe in magnetic field: Quantum dot versus quantum ring behavior. in Physical Review B. 2019;100(12):125304.
doi:10.1103/PhysRevB.100.125304 .

Topalović, Dušan, Arsoski, Vladimir, Tadić, Milan Ž., Peeters, François M., "Confined electron states in two-dimensional HgTe in magnetic field: Quantum dot versus quantum ring behavior" in Physical Review B, 100, no. 12 (2019):125304,
https://doi.org/10.1103/PhysRevB.100.125304 . .

TY  - JOUR
AU  - Topalović, Dušan
AU  - Arsoski, Vladimir
AU  - Pavlović, Suncan
AU  - Čukarić, Nemanja A. 
AU  - Tadić, Milan Ž.
AU  - Peeters, François M.
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/974
AB  - 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.
T2  - Communications in Theoretical Physics
T1  - On Improving Accuracy of Finite-Element Solutions of the Effective-Mass Schrodinger Equation for Interdiffused Quantum Wells and Quantum Wires
VL  - 65
IS  - 1
SP  - 105
EP  - 113
UR  - https://hdl.handle.net/21.15107/rcub_vinar_974
ER  - 

@article{
author = "Topalović, Dušan and Arsoski, Vladimir and Pavlović, Suncan and Čukarić, Nemanja A.  and Tadić, Milan Ž. and Peeters, François M.",
year = "2016",
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.",
journal = "Communications in Theoretical Physics",
title = "On Improving Accuracy of Finite-Element Solutions of the Effective-Mass Schrodinger Equation for Interdiffused Quantum Wells and Quantum Wires",
volume = "65",
number = "1",
pages = "105-113",
url = "https://hdl.handle.net/21.15107/rcub_vinar_974"
}

Topalović, D., Arsoski, V., Pavlović, S., Čukarić, N. A., Tadić, M. Ž.,& Peeters, F. M.. (2016). On Improving Accuracy of Finite-Element Solutions of the Effective-Mass Schrodinger Equation for Interdiffused Quantum Wells and Quantum Wires. in Communications in Theoretical Physics, 65(1), 105-113.
https://hdl.handle.net/21.15107/rcub_vinar_974

Topalović D, Arsoski V, Pavlović S, Čukarić NA, Tadić MŽ, Peeters FM. On Improving Accuracy of Finite-Element Solutions of the Effective-Mass Schrodinger Equation for Interdiffused Quantum Wells and Quantum Wires. in Communications in Theoretical Physics. 2016;65(1):105-113.
https://hdl.handle.net/21.15107/rcub_vinar_974 .

Topalović, Dušan, Arsoski, Vladimir, Pavlović, Suncan, Čukarić, Nemanja A. , Tadić, Milan Ž., Peeters, François M., "On Improving Accuracy of Finite-Element Solutions of the Effective-Mass Schrodinger Equation for Interdiffused Quantum Wells and Quantum Wires" in Communications in Theoretical Physics, 65, no. 1 (2016):105-113,
https://hdl.handle.net/21.15107/rcub_vinar_974 .

TY  - JOUR
AU  - Tomić, Stanko
AU  - Tadić, Milan Ž.
AU  - Milanović, Vitomir B.
AU  - Ikonić, Zoran
PY  - 2000
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2345
AB  - A systematic procedure is described for the maximization of gain in optically pumped intersubband lasers, via optimal tailoring of the quantum well profile. The procedure relies on using the inverse spectral theory, allowing one to shift the bound states as desired, and additionally to make the isospectral reshaping of the well, with the eventual aim of finding the best combination of those optical dipole and electron-phonon scattering matrix elements which are relevant for the laser gain. Example design is presented for a laser based on the AlxGa1-xAs system, and the band nonparabolicity is accounted for in the final design. (C) 2000 American Institute of Physics. [S0021-8979(00)01511-5].
T2  - Journal of Applied Physics
T1  - The optimization of optical gain in the intersubband quantum well laser
VL  - 87
IS  - 11
SP  - 7965
EP  - 7972
DO  - 10.1063/1.373481
ER  - 

@article{
author = "Tomić, Stanko and Tadić, Milan Ž. and Milanović, Vitomir B. and Ikonić, Zoran",
year = "2000",
abstract = "A systematic procedure is described for the maximization of gain in optically pumped intersubband lasers, via optimal tailoring of the quantum well profile. The procedure relies on using the inverse spectral theory, allowing one to shift the bound states as desired, and additionally to make the isospectral reshaping of the well, with the eventual aim of finding the best combination of those optical dipole and electron-phonon scattering matrix elements which are relevant for the laser gain. Example design is presented for a laser based on the AlxGa1-xAs system, and the band nonparabolicity is accounted for in the final design. (C) 2000 American Institute of Physics. [S0021-8979(00)01511-5].",
journal = "Journal of Applied Physics",
title = "The optimization of optical gain in the intersubband quantum well laser",
volume = "87",
number = "11",
pages = "7965-7972",
doi = "10.1063/1.373481"
}

Tomić, S., Tadić, M. Ž., Milanović, V. B.,& Ikonić, Z.. (2000). The optimization of optical gain in the intersubband quantum well laser. in Journal of Applied Physics, 87(11), 7965-7972.
https://doi.org/10.1063/1.373481

Tomić S, Tadić MŽ, Milanović VB, Ikonić Z. The optimization of optical gain in the intersubband quantum well laser. in Journal of Applied Physics. 2000;87(11):7965-7972.
doi:10.1063/1.373481 .

Tomić, Stanko, Tadić, Milan Ž., Milanović, Vitomir B., Ikonić, Zoran, "The optimization of optical gain in the intersubband quantum well laser" in Journal of Applied Physics, 87, no. 11 (2000):7965-7972,
https://doi.org/10.1063/1.373481 . .

TY  - JOUR
AU  - Tomić, Stanko
AU  - Milanović, Vitomir B.
AU  - Tadić, Milan Ž.
AU  - Ikonić, Zoran
PY  - 1999
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2304
AB  - A systematic procedure is described for the maximization of gain in optically pumped intersubband lasers, via tailoring the quantum well potential. The procedure relies on the inverse spectral theory, which enables shifting bound states in a quantum well. By varying the free parameters appearing in this procedure one can design a convenient optimized structure. An design example is presented for an AlxGa1-xAs alloy based well, and the band nonparabolicity effects are accounted for. (C) 1999 Elsevier Science Ltd. All rights reserved.
T2  - Solid State Communications
T1  - Gain optimization in intersubband quantum well lasers by inverse spectral theory
VL  - 113
IS  - 4
SP  - 221
EP  - 226
DO  - 10.1016/S0038-1098(99)00434-2
ER  - 

@article{
author = "Tomić, Stanko and Milanović, Vitomir B. and Tadić, Milan Ž. and Ikonić, Zoran",
year = "1999",
abstract = "A systematic procedure is described for the maximization of gain in optically pumped intersubband lasers, via tailoring the quantum well potential. The procedure relies on the inverse spectral theory, which enables shifting bound states in a quantum well. By varying the free parameters appearing in this procedure one can design a convenient optimized structure. An design example is presented for an AlxGa1-xAs alloy based well, and the band nonparabolicity effects are accounted for. (C) 1999 Elsevier Science Ltd. All rights reserved.",
journal = "Solid State Communications",
title = "Gain optimization in intersubband quantum well lasers by inverse spectral theory",
volume = "113",
number = "4",
pages = "221-226",
doi = "10.1016/S0038-1098(99)00434-2"
}

Tomić, S., Milanović, V. B., Tadić, M. Ž.,& Ikonić, Z.. (1999). Gain optimization in intersubband quantum well lasers by inverse spectral theory. in Solid State Communications, 113(4), 221-226.
https://doi.org/10.1016/S0038-1098(99)00434-2

Tomić S, Milanović VB, Tadić MŽ, Ikonić Z. Gain optimization in intersubband quantum well lasers by inverse spectral theory. in Solid State Communications. 1999;113(4):221-226.
doi:10.1016/S0038-1098(99)00434-2 .

Tomić, Stanko, Milanović, Vitomir B., Tadić, Milan Ž., Ikonić, Zoran, "Gain optimization in intersubband quantum well lasers by inverse spectral theory" in Solid State Communications, 113, no. 4 (1999):221-226,
https://doi.org/10.1016/S0038-1098(99)00434-2 . .