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

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 نشر من قبل Michael A. Zudov
 تاريخ النشر 2015
  مجال البحث فيزياء
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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 $3times 10^4$. 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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