论文标题
手性诱导扭曲双层石墨烯中的巨型单向磁力
Chirality induced Giant Unidirectional Magnetoresistance in Twisted Bilayer Graphene
论文作者
论文摘要
扭曲的双层石墨烯（TBG）表现出引人入胜的相关驱动的现象，例如超导性和莫特绝缘状态，具有平坦的带和手性晶格结构。我们通过量子传输计算发现手性导致TBG中的巨大单向磁磁性（UMR），其中单向性是指在电流或磁场方向的反向下的电阻变化。我们指出，扁平频段可显着增强这种效果。在减小扭转角时，UMR迅速增加，并在10 t的平面磁场中达到1.5 $^\ circ $的角度达到约20 \％。我们提出了带有方向敏感的自由路径的频带结构拓扑（不对称），这是一种预测UMR效应的有用方法。 UMR提供了扭曲双层中的手性和带状度的探针。
Twisted bilayer graphene (TBG) exhibits fascinating correlation-driven phenomena like the superconductivity and Mott insulating state, with flat bands and a chiral lattice structure. We find by quantum transport calculations that the chirality leads to a giant unidirectional magnetoresistance (UMR) in TBG, where the unidirectionality refers to the resistance change under the reversal of the direction of the current or magnetic field. We point out that flat bands significantly enhance this effect. The UMR increases quickly upon reducing the twist angle and reaches about 20\% for an angle of 1.5$^\circ$ in a 10 T in-plane magnetic field. We propose the band structure topology (asymmetry), which leads to a direction-sensitive mean free path, as a useful way to anticipate the UMR effect. The UMR provides a probe for chirality and band flatness in the twisted bilayers.
