title: Tunable spin-orbit interaction in trilayer graphene exemplified in electric-double-layer transistors.
abstract: Taking advantage of ultrahigh electric field generated in electric-double-layer transistors (EDLTs), we investigated spin-orbit interaction (SOI) and its modulation in epitaxial trilayer graphene. It was found in magnetotransport that the dephasing length L(φ) and spin relaxation length L(so) of carriers can be effectively modulated with gate bias. As a direct result, SOI-induced weak antilocalization (WAL), together with a crossover from WAL to weak localization (WL), was observed at near-zero magnetic field. Interestingly, among existing localization models, only the Iordanskii-Lyanda-Geller-Pikus theory can successfully reproduce the obtained magnetoconductance well, serving as evidence for gate tuning of the weak but distinct SOI in graphene. Realization of SOI and its large tunability in the trilayer graphene EDLTs provides us with a possibility to electrically manipulate spin precession in graphene systems without ferromagnetics.
authors.affiliation: Quantum-Phase Electronics Center and Department of Applied Physics, The University of Tokyo, Tokyo 113-8656, Japan.
authors.forename: Zhuoyu
authors.initials: Z
authors.lastname: Chen
authors.forename: Hongtao
authors.initials: H
authors.lastname: Yuan
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Zhang
authors.forename: Kentaro
authors.initials: K
authors.lastname: Nomura
authors.forename: Teng
authors.initials: T
authors.lastname: Gao
authors.forename: Yabo
authors.initials: Y
authors.lastname: Gao
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Shimotani
authors.forename: Zhongfan
authors.initials: Z
authors.lastname: Liu
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Iwasa