Takiguchi Kosuke, Anh Le Duc, Chiba Takahiro, Shiratani Harunori, Fukuzawa Ryota, Takahashi Takuji, Tanaka Masaaki
Department of Electrical Engineering and Information Systems, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8656, Japan.
Institute of Engineering Innovation, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8656, Japan.
Nat Commun. 2022 Nov 9;13(1):6538. doi: 10.1038/s41467-022-34177-w.
According to Onsager's principle, electrical resistance R of general conductors behaves as an even function of external magnetic field B. Only in special circumstances, which involve time reversal symmetry (TRS) broken by ferromagnetism, the odd component of R against B is observed. This unusual phenomenon, called odd-parity magnetoresistance (OMR), was hitherto subtle (< 2%) and hard to control by external means. Here, we report a giant OMR as large as 27% in edge transport channels of an InAs quantum well, which is magnetized by a proximity effect from an underlying ferromagnetic semiconductor (Ga,Fe)Sb layer. Combining experimental results and theoretical analysis using the linearized Boltzmann's equation, we found that simultaneous breaking of both the TRS by the magnetic proximity effect (MPE) and spatial inversion symmetry (SIS) in the one-dimensional (1D) InAs edge channels is the origin of this giant OMR. We also demonstrated the ability to turn on and off the OMR using electrical gating of either TRS or SIS in the edge channels. These findings provide a deep insight into the 1D semiconducting system with a strong magnetic coupling.
根据昂萨格原理，一般导体的电阻R表现为外部磁场B的偶函数。只有在特殊情况下，即涉及由铁磁性破坏的时间反演对称性（TRS）时，才会观察到R相对于B的奇数分量。这种不寻常的现象，称为奇偶磁电阻（OMR），迄今为止很微弱（<2%），并且难以通过外部手段控制。在此，我们报道了在InAs量子阱的边缘输运通道中出现高达27%的巨大OMR，该量子阱通过来自下层铁磁半导体（Ga，Fe）Sb层的近邻效应被磁化。结合使用线性化玻尔兹曼方程的实验结果和理论分析，我们发现一维（1D）InAs边缘通道中由磁近邻效应（MPE）导致的TRS和空间反演对称性（SIS）的同时破缺是这种巨大OMR的起源。我们还展示了通过对边缘通道中的TRS或SIS进行电门控来开启和关闭OMR的能力。这些发现为具有强磁耦合的一维半导体系统提供了深入见解。
