In-plane hole $g$ factors measured in quantum point contacts based on $p$-type heterostructures strongly depend on the orientation of the magnetic field with respect to the electric current. This effect, first reported a decade ago and confirmed in a number of publications, has remained an open problem. In this work, we present systematic experimental studies to disentangle different mechanisms contributing to the effect and develop the theory which describes it successfully. We show that there is a new mechanism for the anisotropy related to the existence of an additional $B_{+}{k}_{-}^4{\sigma }_{+}$ effective Zeeman interaction for holes, which is kinematically different from the standard single Zeeman term $B_{-}{k}_{-}^2{\sigma }_{+}$ considered until now.

中文翻译：

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基于空穴的量子点接触中平面内因子的强各向异性机理

面内孔 $G$ 在量子点接触中测量的因素基于 $p$型异质结构在很大程度上取决于磁场相对于电流的方向。这种效应在十年前首次报道，并在许多出版物中得到证实，但仍然是一个未解决的问题。在这项工作中，我们目前进行系统的实验研究，以弄清造成这种现象的不同机制，并发展成功描述这种现象的理论。我们表明，存在与各向异性有关的新机制${乙}_{+}{ķ}_{-}^4{\sigma }_{+}$ 孔的有效塞曼相互作用，在运动学上不同于标准的单个塞曼术语 ${乙}_{-}{ķ}_{-}^{\mathrm{2个}}{\sigma }_{+}$ 考虑到现在。