title: Direct observation of spin-layer locking by local Rashba effect in monolayer semiconducting PtSe2film.
abstract: The generally accepted view that spin polarization in non-magnetic solids is induced by the asymmetry of the global crystal space group has limited the search for spintronics materials mainly to non-centrosymmetric materials. In recent times it has been suggested that spin polarization originates fundamentally from local atomic site asymmetries and therefore centrosymmetric materials may exhibit previously overlooked spin polarizations. Here, by using spin- and angle-resolved photoemission spectroscopy, we report the observation of helical spin texture in monolayer, centrosymmetric and semiconducting PtSe2film without the characteristic spin splitting in conventional Rashba effect (R-1). First-principles calculations and effective analytical model analysis suggest local dipole induced Rashba effect (R-2) with spin-layer locking: opposite spins are degenerate in energy, while spatially separated in the top and bottom Se layers. These results not only enrich our understanding of the spin polarization physics but also may find applications in electrically tunable spintronics.
authors.affiliation: State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China.
authors.forename: Wei
authors.identifier: 0000-0003-4518-3632
authors.initials: W
authors.lastname: Yao
authors.affiliation: State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China.
authors.forename: Eryin
authors.initials: E
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China.
authors.forename: Huaqing
authors.initials: H
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Deng
authors.affiliation: State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China.
authors.forename: Mingzhe
authors.initials: M
authors.lastname: Yan
authors.affiliation: State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China.
authors.forename: Kenan
authors.initials: K
authors.lastname: Zhang
authors.affiliation: Hiroshima Synchrotron Radiation Center (HSRC), Hiroshima University, 2-313 Kagamiyama, Higashi-Hiroshima 739-0046, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Miyamoto
authors.affiliation: Hiroshima Synchrotron Radiation Center (HSRC), Hiroshima University, 2-313 Kagamiyama, Higashi-Hiroshima 739-0046, Japan.
authors.forename: Taichi
authors.initials: T
authors.lastname: Okuda
authors.affiliation: Institute of Physics &University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Linfei
authors.initials: L
authors.lastname: Li
authors.affiliation: Institute of Physics &University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.|Collaborative Innovation Center of Quantum Matter, Beijing, China.
authors.forename: Yeliang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Institute of Physics &University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.|Collaborative Innovation Center of Quantum Matter, Beijing, China.
authors.forename: Hongjun
authors.initials: H
authors.lastname: Gao
authors.affiliation: Department of Physics, The Pennsylvania State University, University Park, State College, Pennsylvania 16802-6300, USA.
authors.forename: Chaoxing
authors.initials: C
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China.|Collaborative Innovation Center of Quantum Matter, Beijing, China.
authors.forename: Wenhui
authors.initials: W
authors.lastname: Duan
authors.affiliation: State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China.|Collaborative Innovation Center of Quantum Matter, Beijing, China.
authors.forename: Shuyun
authors.initials: S
authors.lastname: Zhou