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arXiv · 1906.03478

Anomalous Decay of Quantum Resistance Oscillations of Two Dimensional Helical Electrons in Magnetic Field

S. Abedi·S. A. Vitkalov·N. N. Mikhailov·Z. D. Kvon
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Abstract

Shubnikov de Haas resistance oscillations of highly mobile two dimensional helical electrons propagating on a conducting surface of strained HgTe 3D topological insulator are studied in magnetic fields B tilted by angle $θ$ from the normal to the conducting layer. Strong decrease of oscillation amplitude A is observed with the tilt: $A \sim \exp(-ξ/cos(θ))$, where $ξ$ is a constant. Evolution of the oscillations with temperature T shows that the parameter $ξ$ contains two terms: $ξ=ξ_1+ξ_2 T$. The temperature independent term, $ξ_1$, describes reduction of electron mean free path in magnetic field B pointing toward suppression of the topological protection of the electron states against impurity scattering. The temperature dependent term, $ξ_2 T$, indicates increase of the reciprocal velocity of 2D helical electrons suggesting modification of the electron spectrum in magnetic fields.

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S. Abedi, S. A. Vitkalov, N. N. Mikhailov, Z. D. Kvon. 2019-06-08. Anomalous Decay of Quantum Resistance Oscillations of Two Dimensional Helical Electrons in Magnetic Field. https://doi.org/10.1038/s41598-020-64385-7

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