Giant asymmetric proximity-induced spin-orbit coupling in twisted graphene/SnTe heterostructure
arxiv(2024)
摘要
We analyze the spin-orbit coupling effects in a three-degree twisted bilayer
heterostructure made of graphene and an in-plane ferroelectric SnTe, with the
goal of transferring the spin-orbit coupling from SnTe to graphene, via the
proximity effect. Our results indicate that the point-symmetry breaking due to
the incompatible mutual symmetry of the twisted monolayers and a strong
hybridization has a massive impact on the spin splitting in graphene close to
the Dirac point, with the spin splitting values greater than 20 meV. The band
structure and spin expectation values of graphene close to the Dirac point can
be described using a symmetry-free model, triggering different types of
interaction with respect to the threefold symmetric graphene/transition-metal
dichalcogenide heterostructure. We show that the strong hybridization of the
Dirac cone's right movers with the SnTe band gives rise to a large asymmetric
spin splitting in the momentum space. Furthermore, we discover that the
ferroelectricity-induced Rashba spin-orbit coupling in graphene is the dominant
contribution to the overall Rashba field, with the effective in-plane electric
field that is almost aligned with the (in-plane) ferroelectricity direction of
the SnTe monolayer. We also predict an anisotropy of the in-plane spin
relaxation rates. Our results demonstrate that the group-IV monochalcogenides
MX (M=Sn, Ge; X=S, Se, Te) are a viable alternative to transition-metal
dichalcogenides for inducing strong spin-orbit coupling in graphene.
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要