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Temperature-Induced Topological Phase Transition in HgTe Quantum Wells 
Auteur(s): Kadykov A., Krishtopenko S., Jouault B., Desrat W., Knap W., Ruffenach S., Consejo C., Torres J., Morozov S. V., Mikhailov N. N., Dvoretskii S. A., Teppe F.
(Article) Publié:
Physical Review Letters, vol. 120 p.086401 (2018)
Texte intégral en Openaccess : 
Ref HAL: hal-01740166_v1
Ref Arxiv: 1710.06666
DOI: 10.1103/PhysRevLett.120.086401
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote
Résumé: We report a direct observation of temperature-induced topological phase transition between trivial and topological insulator in HgTe quantum well. By using a gated Hall bar device, we measure and represent Landau levels in fan charts at different temperatures and we follow the temperature evolution of a peculiar pair of "zero-mode" Landau levels, which split from the edge of electron-like and hole-like subbands. Their crossing at critical magnetic field $B_c$ is a characteristic of inverted band structure in the quantum well. By measuring the temperature dependence of $B_c$, we directly extract the critical temperature $T_c$, at which the bulk band-gap vanishes and the topological phase transition occurs. Above this critical temperature, the opening of a trivial gap is clearly observed.
Commentaires: 5 pages + Supplemental Materials; Phys. Rev. Lett. (accepted). Réf Journal: Phys. Rev. Lett. 120, 086401 (2018)
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