We report on strong transport anisotropy in a two-dimensional 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 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.

• Received 27 August 2014
• Revised 18 February 2015

DOI:https://doi.org/10.1103/PhysRevB.91.201301