Gate-Tunable Reversible Rashba−Edelstein Effect in a Few-Layer Graphene/2H-TaS2 Heterostructure at Room Temperature

TY - JOUR

T1 - Gate-Tunable Reversible Rashba−Edelstein Effect in a Few-Layer Graphene/2H-TaS2 Heterostructure at Room Temperature

AU - Li, Lijun

AU - Zhang, Jin

AU - Myeong, Gyuho

AU - Shin, Wongil

AU - Lim, Hongsik

AU - Kim, Boram

AU - Kim, Seungho

AU - Jin, Taehyeok

AU - Cavill, Stuart Alan

AU - Kim, Beom Seo

AU - Kim, Changyoung

AU - Lischner, Johannes

AU - Ferreira, Aires

AU - Cho, Sungjae

N1 - © 2020 American Chemical Society. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details.

PY - 2020/5/26

Y1 - 2020/5/26

N2 - We report the observation of current-induced spin polarization, the Rashba−Edelstein effect (REE), and its Onsager reciprocal phenomenon, the spin galvanic effect (SGE), in a few-layer graphene/2H-TaS2 heterostructure at room temperature. Spin-sensitive electrical measurements unveil full spin-polarization reversal by an applied gate voltage. The observed gate-tunable charge-to-spin conversion is explained by the ideal work function mismatch between 2H-TaS2 and graphene, which allows for a strong interface-induced Bychkov−Rashba interaction with a spin-gap reaching 70 meV, while keeping the Dirac nature of the spectrum intact across electron and hole sectors. The reversible electrical generation and control of the nonequilibrium spin polarization vector, not previously observed in a nonmagnetic material, are elegant manifestations of emergent two-dimensional Dirac Fermions with robust spin-helical structure. Our experimental findings, supported by first-principles relativistic electronic structure and transport calculations, demonstrate a route to design low-power spin−logic circuits from layered materials.

AB - We report the observation of current-induced spin polarization, the Rashba−Edelstein effect (REE), and its Onsager reciprocal phenomenon, the spin galvanic effect (SGE), in a few-layer graphene/2H-TaS2 heterostructure at room temperature. Spin-sensitive electrical measurements unveil full spin-polarization reversal by an applied gate voltage. The observed gate-tunable charge-to-spin conversion is explained by the ideal work function mismatch between 2H-TaS2 and graphene, which allows for a strong interface-induced Bychkov−Rashba interaction with a spin-gap reaching 70 meV, while keeping the Dirac nature of the spectrum intact across electron and hole sectors. The reversible electrical generation and control of the nonequilibrium spin polarization vector, not previously observed in a nonmagnetic material, are elegant manifestations of emergent two-dimensional Dirac Fermions with robust spin-helical structure. Our experimental findings, supported by first-principles relativistic electronic structure and transport calculations, demonstrate a route to design low-power spin−logic circuits from layered materials.

KW - graphene

KW - 2D materials

KW - edelstein effect

KW - Rashba edelstein effect

KW - spin galvanic effect

KW - spintronics

U2 - 10.1021/acsnano.0c01037

DO - 10.1021/acsnano.0c01037

M3 - Article

SN - 1936-0851

VL - 14

SP - 5251

EP - 5259

JO - ACS Nano

JF - ACS Nano

IS - 5

ER -