TY  - CONF
AU  - Topalović, Dušan
AU  - Arsoski, Vladimir V.
AU  - Tadić, Milan Ž.
AU  - Peeters, François M.
PY  - 2019
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/11878
AB  - The quantum spin Hall (QSH) effect is a unique phase of matter characterized by a pair of helical edge states protected by time-reversal symmetry. The existence of this phase was first theoretically proposed for graphene [1]. However, experiments showed that spin-orbit interaction in low-mass C atoms is too small to open an energy gap [2]. Therefore, greater attention is paid to materials that are composed of heavier atoms in which relativistic effects are more pronounced. A notable example is thin HgTe/CdTe quantum well (QW) where the QSH effect was theoretically predicted [3] and experimentally realized [4]. By using effective models it has been found that double symmetric HgTe/CdxHg1-xTe QW may also possess a topological nontrivial phase [5, 6]. Structures of this type exhibit interesting 3/2 pseudospin based physics similar to that in bilayer graphene without valley degeneracy [6]. We investigate the electronic properties of double asymmetric HgTe/CdxHg1-xTe QW with [001] orientation. The electronic structure is calculated within the framework of the Kane k · p theory [7]. We choose the common eight-band basis set that describes the coupling between the Γ6, Γ7, and Γ8 bands. We assumed that the model parameters change abruptly along the structure. Also, the difference between the valence bands in HgTe and CdTe is assumed to vary linearly with mole fraction. The theoretical model is based on the Burt envelope function approach on expansion in plane waves is used in our numerical calculations. The results obtained for the electronic structure indicate that a quantum phase transition can occur in asymmetric double QW when a perpendicular electric field is applied. Besides an external field the phase transition could be controlled by varying geometric parameters of the wells and the mole fraction in barriers.
PB  - Belgrade : Vinča Institute of Nuclear Sciences, University of Belgrade
C3  - PHOTONICA2019 : 7th International School and Conference on Photonics & Machine Learning with Photonics Symposium : Book of abstracts
T1  - Tunable quantum phase transitions in asymmetric HgTe/CdxHg1-xTe double quantum wells
SP  - 109
EP  - 109
UR  - https://hdl.handle.net/21.15107/rcub_vinar_11878
ER  - 

@conference{
author = "Topalović, Dušan and Arsoski, Vladimir V. and Tadić, Milan Ž. and Peeters, François M.",
year = "2019",
abstract = "The quantum spin Hall (QSH) effect is a unique phase of matter characterized by a pair of helical edge states protected by time-reversal symmetry. The existence of this phase was first theoretically proposed for graphene [1]. However, experiments showed that spin-orbit interaction in low-mass C atoms is too small to open an energy gap [2]. Therefore, greater attention is paid to materials that are composed of heavier atoms in which relativistic effects are more pronounced. A notable example is thin HgTe/CdTe quantum well (QW) where the QSH effect was theoretically predicted [3] and experimentally realized [4]. By using effective models it has been found that double symmetric HgTe/CdxHg1-xTe QW may also possess a topological nontrivial phase [5, 6]. Structures of this type exhibit interesting 3/2 pseudospin based physics similar to that in bilayer graphene without valley degeneracy [6]. We investigate the electronic properties of double asymmetric HgTe/CdxHg1-xTe QW with [001] orientation. The electronic structure is calculated within the framework of the Kane k · p theory [7]. We choose the common eight-band basis set that describes the coupling between the Γ6, Γ7, and Γ8 bands. We assumed that the model parameters change abruptly along the structure. Also, the difference between the valence bands in HgTe and CdTe is assumed to vary linearly with mole fraction. The theoretical model is based on the Burt envelope function approach on expansion in plane waves is used in our numerical calculations. The results obtained for the electronic structure indicate that a quantum phase transition can occur in asymmetric double QW when a perpendicular electric field is applied. Besides an external field the phase transition could be controlled by varying geometric parameters of the wells and the mole fraction in barriers.",
publisher = "Belgrade : Vinča Institute of Nuclear Sciences, University of Belgrade",
journal = "PHOTONICA2019 : 7th International School and Conference on Photonics & Machine Learning with Photonics Symposium : Book of abstracts",
title = "Tunable quantum phase transitions in asymmetric HgTe/CdxHg1-xTe double quantum wells",
pages = "109-109",
url = "https://hdl.handle.net/21.15107/rcub_vinar_11878"
}

Topalović, D., Arsoski, V. V., Tadić, M. Ž.,& Peeters, F. M.. (2019). Tunable quantum phase transitions in asymmetric HgTe/CdxHg1-xTe double quantum wells. in PHOTONICA2019 : 7th International School and Conference on Photonics & Machine Learning with Photonics Symposium : Book of abstracts
Belgrade : Vinča Institute of Nuclear Sciences, University of Belgrade., 109-109.
https://hdl.handle.net/21.15107/rcub_vinar_11878

Topalović D, Arsoski VV, Tadić MŽ, Peeters FM. Tunable quantum phase transitions in asymmetric HgTe/CdxHg1-xTe double quantum wells. in PHOTONICA2019 : 7th International School and Conference on Photonics & Machine Learning with Photonics Symposium : Book of abstracts. 2019;:109-109.
https://hdl.handle.net/21.15107/rcub_vinar_11878 .

Topalović, Dušan, Arsoski, Vladimir V., Tadić, Milan Ž., Peeters, François M., "Tunable quantum phase transitions in asymmetric HgTe/CdxHg1-xTe double quantum wells" in PHOTONICA2019 : 7th International School and Conference on Photonics & Machine Learning with Photonics Symposium : Book of abstracts (2019):109-109,
https://hdl.handle.net/21.15107/rcub_vinar_11878 .