论文标题
石墨烯中的山谷电流通过电子 - phonon相互作用
Valley current in graphene through electron-phonon interaction
论文作者
论文摘要
我们讨论了山谷电流，该电流由石墨烯中的准粒子携带。我们表明，山谷电流是由于电子 - phonon碰撞积分中的特殊项而产生的，该术语将标量和矢量规范的类似于电子 - phonon相互作用的顶点混合在一起。这种混合使声子与对手性敏感的电子的碰撞，这在两个山谷中相反。由于与声子发生碰撞，不同山谷的电子偏相偏离。不需要打破空间反演对称性，而对于山谷的依赖性偏差偏差。这种效应既存在于原始石墨烯或双层石墨烯样品中，并且由于在较高温度下与声子的碰撞率较高，因此随温度的增加而增加。可以通过使用合适设计的非局部变压器测量电流来检测到准颗粒携带的山谷电流。
We discuss valley current, which is carried by quasiparticles in graphene. We show that the valley current arises owing to a peculiar term in the electron-phonon collision integral that mixes the scalar and vector gauge-field-like vertices in the electron-phonon interaction. This mixing makes collisions of phonons with electrons sensitive to their chirality, which is opposite in two valleys. As a result of collisions with phonons, electrons of the different valleys deviate in opposite directions. Breaking the spatial inversion symmetry is not needed for a valley-dependent deviation of the quasiparticle current. The effect exists both in pristine graphene or bilayer graphene samples, and it increases with temperature owing to a higher rate of collisions with phonons at higher temperatures. The valley current carried by quasiparticles could be detected by measuring the electric current using a nonlocal transformer of a suitable design.
