Tunable spin–orbit coupling and symmetry-protected edge states in graphene/WS2

By Bowen Yang, Min-Feng Tu, Jeongwoo Kim, Yong Wu, Hui Wang, J. Alicea, R. Wu, M. Bockrath, Jing Shi. 2016

153 citations recorded by the source corpus.

We demonstrate clear weak anti-localization (WAL) effect arising from induced Rashba spin–orbit coupling (SOC) in WS2-covered single-layer and bilayer graphene devices. Contrary to the uncovered region of a shared single-layer graphene flake, WAL in WS2-covered graphene occurs over a wide range of carrier densities on both electron and hole sides. At high carrier densities, we estimate the Rashba SOC relaxation rate to be ∼ 0.2 ps − 1 and show that it can be tuned by transverse electric fields. In addition to the Rashba SOC, we also predict the existence of a‘valley-Zeeman’ SOC from first-principles calculations. The interplay between these two SOC’s can open a non-topological but interesting gap in graphene; in particular, zigzag boundaries host four sub-gap edge states protected by time-reversal and crystalline symmetries. The graphene/WS2 system provides a possible platform for these novel edge states.

Subfields: Atomic and Molecular Physics, and Optics, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/5e2a098efc9282d26f3e2287b42326fe4536708c

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Atomic and Molecular Physics, and Optics

In Materials Chemistry

Citations in the corpus

Origin and magnitude of 'designer' spin-orbit interaction in graphene on semiconducting transition metal dichalcogenides (2016, unknown): “the conductivity of graphene [18,19]—confirm these”
Colloquium : Spintronics in graphene and other two-dimensional materials (2019, background): “2): in general, two (instead of one) pairs of sub-gap helical modes connected by time-reversal symmetry appear at the boundaries of the system (Yang et al., 2016).”