Wawrzyńczak R, Galeski S, Noky J, Sun Y, Felser C, Gooth J
Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany.
Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany.
Sci Rep. 2022 Feb 9;12(1):2153. doi: 10.1038/s41598-022-05916-2.
The quasi-quantized Hall effect (QQHE) is the three-dimensional (3D) counterpart of the integer quantum Hall effect (QHE), exhibited only by two-dimensional (2D) electron systems. It has recently been observed in layered materials, consisting of stacks of weakly coupled 2D platelets that are yet characterized by a 3D anisotropic Fermi surface. However, it is predicted that the quasi-quantized 3D version of the 2D QHE should occur in a much broader class of bulk materials, regardless of the underlying crystal structure. Here, we compare the observation of quasi-quantized plateau-like features in the Hall conductivity of the n-type bulk semiconductor InAs with the predictions for the 3D QQHE in presence of parabolic electron bands. InAs takes form of a cubic crystal without any low-dimensional substructure. The onset of the plateau-like feature in the Hall conductivity scales with [Formula: see text] in units of the conductance quantum and is accompanied by a Shubnikov-de Haas minimum in the longitudinal resistivity, consistent wit the results of calculations. This confirms the suggestion that the 3D QQHE may be a generic effect directly observable in materials with small Fermi surfaces, placed in sufficiently strong magnetic fields.
准量子化霍尔效应（QQHE）是整数量子霍尔效应（QHE）的三维（3D）对应物，仅由二维（2D）电子系统表现出来。最近在层状材料中观察到了它，这种材料由弱耦合二维薄片堆叠而成，但具有三维各向异性费米面。然而，据预测，二维QHE的准量子化三维版本应该会出现在更广泛的一类块状材料中，而与底层晶体结构无关。在这里，我们将n型块状半导体InAs霍尔电导率中准量子化的类似平台特征的观测结果与存在抛物线型电子能带时三维QQHE的预测结果进行比较。InAs呈立方晶体形式，没有任何低维子结构。霍尔电导率中类似平台特征的起始以电导量子为单位与[公式：见原文]成比例，并且伴随着纵向电阻率中的舒布尼科夫 - 德哈斯最小值，这与计算结果一致。这证实了以下观点：三维QQHE可能是一种在具有小费米面的材料中，置于足够强磁场下可直接观测到的普遍效应。
