Zhu Wenxuan, Song Cheng, Han Lei, Guo Tingwen, Bai Hua, Pan Feng
Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Beijing Innovation Center for Future Chips, Tsinghua University, Beijing, 100084, China.
Nat Commun. 2022 Oct 28;13(1):6428. doi: 10.1038/s41467-022-34193-w.
Recent discovery of two-dimensional (2D) magnets with van der Waals (vdW) gapped layered structure prospers the fundamental research of magnetism and advances the miniaturization of spintronics. Due to their unique lattice anisotropy, their band structure has the potential to be dramatically modulated by the spin configuration even in thin flakes, which is still unexplored. Here, we demonstrate the vdW lattice-induced spin modulation of band structure in thin flakes of vdW semiconductor CrGeTe (CGT) through the measurement of magnetoresistance (MR). The significant anisotropic lattice constructed by the interlayer vdW force and intralayer covalent bond induces anisotropic spin-orbit field, resulting in the spin orientation-dependent band splitting. Consequently, giant variation of resistance is induced between the magnetization aligned along in-plane and out-of-plane directions. Based on this, a colossal MR beyond 1000% was realized in lateral nonlocal devices with CGT acting as a magneto switch. Our finding provides a unique feature for the vdW magnets and would advance its applications in spintronics.
具有范德华（vdW）能隙层状结构的二维（2D）磁体的最新发现推动了磁学的基础研究，并促进了自旋电子学的小型化。由于其独特的晶格各向异性，即使在薄片中，其能带结构也有可能被自旋构型显著调制，而这一点仍未被探索。在此，我们通过磁电阻（MR）测量，展示了范德华半导体CrGeTe（CGT）薄片中vdW晶格诱导的能带结构自旋调制。由层间vdW力和层内共价键构成的显著各向异性晶格会诱导各向异性自旋轨道场，导致能带分裂与自旋取向相关。因此，在沿面内和面外方向排列的磁化之间会引起电阻的巨大变化。基于此，在以CGT作为磁开关的横向非局部器件中实现了超过1000%的巨大磁电阻。我们的发现为vdW磁体提供了一个独特特性，并将推动其在自旋电子学中的应用。
