Graphene on transition-metal dichalcogenides: A platform for proximity spin-orbit physics and optospintronics
Graphene on transition-metal dichalcogenides: A platform for proximity spin-orbit physics and optospintronics
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DOI：
10.1103/physrevb.92.155403
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发表时间：
2015-10-05
影响因子：
3.7
通讯作者：
Fabian, Jaroslav
中科院分区：
文献类型：
--
作者：
Gmitra, Martin;Fabian, Jaroslav
石墨烯和二维过渡金属二硫属化物（TMDC）的混合物有可能将石墨烯自旋电子学提升到一个新的水平。正如我们在这里通过对单层MoS 2上的石墨烯进行第一原理计算所示，这种混合物相对于原始石墨烯有几个优点。首先，石墨烯中的狄拉克电子表现出巨大的全局邻近自旋轨道耦合，而不会在零场下损害整个系统的半金属特性。值得注意的是，这些自旋轨道效应可以非常准确地描述一个简单的有效哈密顿量。第二，费米能级可以通过横向电场来调谐，以穿过二硫化钼导带，从而产生耦合的大质量和无质量电子气体系统。在这样的系统中，电荷和自旋输运都应该是唯一的。最后，我们建议使用石墨烯/TMDC结构作为光自旋电子学的平台，特别是用于将光自旋注入石墨烯和用于研究TMDC与石墨烯之间的自旋转移。
Hybrids of graphene and two-dimensional transition-metal dichalcogenides (TMDCs) have the potential to bring graphene spintronics to the next level. As we show here by performing first-principles calculations of graphene on monolayer MoS2, there are several advantages of such hybrids over pristine graphene. First, Dirac electrons in graphene exhibit a giant global proximity spin-orbit coupling, without compromising the semimetallic character of the whole system at zero field. Remarkably, these spin-orbit effects can be very accurately described by a simple effective Hamiltonian. Second, the Fermi level can be tuned by a transverse electric field to cross the MoS2 conduction band, creating a system of coupled massive and massless electron gases. Both charge and spin transport in such systems should be unique. Finally, we propose to use graphene/TMDC structures as a platform for optospintronics, in particular, for optical spin injection into graphene and for studying spin transfer between TMDCs and graphene.