TY - JOUR

T1 - Two-dimensional topological Anderson insulator in a HgTe-based semimetal

AU - Khudaiberdiev, D. A.

AU - Kvon, Z. D.

AU - Ryzhkov, M. S.

AU - Kozlov, D. A.

AU - Mikhailov, N. N.

AU - Pimenov, A.

N1 - Acknowledgments. The authors acknowledge the TU Wien Bibliothek for financial support through its Open Access Funding Programme and the Russian Science Foundation (Grant No. 23-72-30003).

PY - 2025/5/9

Y1 - 2025/5/9

N2 - In strongly disordered HgTe quantum wells with a semimetallic spectrum we have experimentally discovered Anderson localization of two-dimensional (2D) electrons and holes in the bulk of the quantum well, exhibiting an exponentially strong increase in resistance as the temperature decreases. Conversely, for the one-dimensional (1D) edge current states we observed a very weak temperature dependence of the resistance, indicating the absence of localization. Initially the system is a bulk conductor, but a strong disorder opens the mobility gap in the bulk, which leads to the formation of a 2D topological Anderson insulator (TAI) state. This state turned out to be very sensitive to the applied perpendicular to the system's plane magnetic field. Firstly, a small magnetic field of 30mT breaks the topological protection of 1D edge channels turning the system into an ordinary Anderson insulator. Secondly, the magnetic field of 0.5T delocalizes 2D bulk electrons, transitioning the system into a quantum Hall liquid.

AB - In strongly disordered HgTe quantum wells with a semimetallic spectrum we have experimentally discovered Anderson localization of two-dimensional (2D) electrons and holes in the bulk of the quantum well, exhibiting an exponentially strong increase in resistance as the temperature decreases. Conversely, for the one-dimensional (1D) edge current states we observed a very weak temperature dependence of the resistance, indicating the absence of localization. Initially the system is a bulk conductor, but a strong disorder opens the mobility gap in the bulk, which leads to the formation of a 2D topological Anderson insulator (TAI) state. This state turned out to be very sensitive to the applied perpendicular to the system's plane magnetic field. Firstly, a small magnetic field of 30mT breaks the topological protection of 1D edge channels turning the system into an ordinary Anderson insulator. Secondly, the magnetic field of 0.5T delocalizes 2D bulk electrons, transitioning the system into a quantum Hall liquid.

UR - http://arxiv.org/abs/2410.23564

UR - https://www.mendeley.com/catalogue/854003f2-c890-33fa-b60e-e6f09d33342c/

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-105005260550&origin=inward&txGid=2fabe9a78ee89cd6cc3c867e1e55666a

U2 - 10.1103/PhysRevResearch.7.L022033

DO - 10.1103/PhysRevResearch.7.L022033

M3 - Article

JO - Physical Review Research

JF - Physical Review Research

SN - 2643-1564

M1 - L022033

ER -