Department of Chemistry, Columbia University, New York, NY, USA.
Department of Physics, Columbia University, New York, NY, USA.
Nat Mater. 2022 Jul;21(7):754-760. doi: 10.1038/s41563-022-01245-x. Epub 2022 May 5.
Semiconductors, featuring tunable electrical transport, and magnets, featuring tunable spin configurations, form the basis of many information technologies. A long-standing challenge has been to realize materials that integrate and connect these two distinct properties. Two-dimensional (2D) materials offer a platform to realize this concept, but known 2D magnetic semiconductors are electrically insulating in their magnetic phase. Here we demonstrate tunable electron transport within the magnetic phase of the 2D semiconductor CrSBr and reveal strong coupling between its magnetic order and charge transport. This provides an opportunity to characterize the layer-dependent magnetic order of CrSBr down to the monolayer via magnetotransport. Exploiting the sensitivity of magnetoresistance to magnetic order, we uncover a second regime characterized by coupling between charge carriers and magnetic defects. The magnetoresistance within this regime can be dynamically and reversibly tuned by varying the carrier concentration using an electrostatic gate, providing a mechanism for controlling charge transport in 2D magnets.
半导体具有可调谐的电子输运特性，而磁铁具有可调谐的自旋配置特性，它们是许多信息技术的基础。长期以来的一个挑战是实现将这两种截然不同的特性集成和连接起来的材料。二维（2D）材料为实现这一概念提供了一个平台，但已知的 2D 磁性半导体在其磁性相是电绝缘的。在这里，我们展示了 2D 半导体 CrSBr 中在磁性相内可调谐的电子输运，并揭示了其磁有序和电荷输运之间的强耦合。这为通过磁输运来表征 CrSBr 的层依赖磁有序提供了机会。利用磁阻对磁有序的敏感性，我们发现了第二个特征，即载流子与磁缺陷之间的耦合。通过使用静电门改变载流子浓度，可以动态和可逆地调节该磁阻，为控制 2D 磁铁中的电荷输运提供了一种机制。
