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arXiv · 1712.03454

Diagnosing the magnetic field-tuned symmetry nature of the topological electrons by conductance fluctuations in bulk-insulating BiSbTeSe2 devices

Shuai Zhang·Faji Xie·Xing-Chen Pan·Yuyuan Qin·Lu Cao·Xuefeng Wang·Fengqi Song·Baigeng Wang
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Abstract

We extract the quantum conductance fluctuations and study its magnetic field dependence in the gate-dependent transport of the topological electrons in bulk-insulating BiSbTeSe2 devices. While increasing the magnetic field from 0 to 12 Tesla, the fluctuation magnitudes are found reduced by a ratio of sqrt(2) and form a quantized step. The step is observed both in n-type and p-type transport. It is also confirmed in the nonlocal measurements. This essentially demonstrates the breaking of the time reversal symmetry of the three-dimensional Z2 topological insulators.

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Shuai Zhang, Faji Xie, Xing-Chen Pan, Yuyuan Qin, Lu Cao, Xuefeng Wang, Fengqi Song, Baigeng Wang. 2017-12-10. Diagnosing the magnetic field-tuned symmetry nature of the topological electrons by conductance fluctuations in bulk-insulating BiSbTeSe2 devices. https://doi.org/10.1063/1.5031013

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