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arXiv · 1511.05167

Strong Transport Anisotropy in a Ge/SiGe Quantum Well in Tilted Magnetic Fields

Q. Shi·M. A. Zudov·C. Morrison·M. Myronov
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Abstract

We report on a strong transport anisotropy in a 2D hole gas in a Ge/SiGe quantum well, which emerges only when both perpendicular and in-plane magnetic fields are present. The ratio of resistances, measured along and perpendicular to the in-plane field, can exceed $3\times 10^4$. The anisotropy occurs in a wide range of filling factors where it is determined {\em primarily} by the tilt angle. The lack of significant anisotropy without an in-plane field, easy tunability, and persistence to higher temperatures and filling factors set this anisotropy apart from nematic phases in GaAs/AlGaAs.

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Q. Shi, M. A. Zudov, C. Morrison, M. Myronov. 2015-11-16. Strong Transport Anisotropy in a Ge/SiGe Quantum Well in Tilted Magnetic Fields. https://doi.org/10.1103/physrevb.91.201301

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