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arXiv · 2208.06050

Magneto-anisotropic weak antilocalization in near-surface quantum wells

S. M. Farzaneh·Mehdi Hatefipour·William F. Schiela·Neda Lotfizadeh·Peng Yu·Bassel Heiba Elfeky·William M. Strickland·Alex Matos-Abiague·Javad Shabani
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Abstract

We investigate the effects of an in-plane magnetic field on the weak antilocalization signature of near-surface quantum wells lacking bulk and inversion symmetry. The measured magnetoconductivity exhibits a strong anisotropy with respect to the direction of the in-plane magnetic field. The two-fold symmetry of the observed magneto-anisotropy originates from the competition between Rashba and Dresselhaus spin-orbit couplings. The high sensitivity of the weak antilocalization to the spin texture produced by the combined Zeeman and spin-orbit fields results in very large anisotropy ratios, reaching 100%. Using a semiclassical universal model in quantitative agreement with the experimental data, we uniquely determine the values of the Dresselhaus and Rashba parameters as well as the effective in-plane g-factor of the electrons. Understanding these parameters provides new prospects for novel applications ranging from spintronics to topological quantum computing.

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S. M. Farzaneh, Mehdi Hatefipour, William F. Schiela, Neda Lotfizadeh, Peng Yu, Bassel Heiba Elfeky, William M. Strickland, Alex Matos-Abiague, Javad Shabani. 2022-11-14. Magneto-anisotropic weak antilocalization in near-surface quantum wells. https://doi.org/10.1103/physrevresearch.6.013039

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