Spatial Separation of Carrier Spin by the Valley Hall Effect in Monolayer WSe2 Transistors

Barré, Elyse; Incorvia, Jean Anne C.; Kim, Suk Hyun; McClellan, Connor J.; Pop, Eric; Wong, H. -S. Philip; Heinz, Tony F.

doi:10.1021/acs.nanolett.8b03838

Spatial Separation of Carrier Spin by the Valley Hall Effect in Monolayer WSe₂ Transistors

Journal Article · Wed Jan 02 00:00:00 EST 2019 · Nano Letters

DOI:https://doi.org/10.1021/acs.nanolett.8b03838· OSTI ID:1507158

^[1]; Incorvia, Jean Anne C. ^[2]; Kim, Suk Hyun ^[1]; ^[1]; ^[1]; Wong, H. -S. Philip ^[1]; Heinz, Tony F. ^[1]

Stanford Univ., Stanford, CA (United States)
Stanford Univ., Stanford, CA (United States); Univ. of Texas at Austin, Austin, TX (United States)

We investigate the valley Hall effect (VHE) in monolayer WSe₂ field-effect transistors using optical Kerr rotation measurements at 20 K. While studies of the VHE have so far focused on n-doped MoS₂, we observe the VHE in WSe₂ in both the n- and p-doping regimes. Hole doping enables access to the large spin-splitting of the valence band of this material. The Kerr rotation measurements probe the spatial distribution of the valley carrier imbalance induced by the VHE. Under current flow, we observe distinct spin-valley polarization along the edges of the transistor channel. From analysis of the magnitude of the Kerr rotation, we infer a spin-valley density of 44 spins/μm, integrated over the edge region in the p-doped regime. As a result, assuming a spin diffusion length less than 0.1 μm, this corresponds to a spin-valley polarization of the holes exceeding 1%.

View Accepted Manuscript (DOE)

Research Organization:: SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)

Sponsoring Organization:: USDOE

Grant/Contract Number:: AC02-76SF00515

OSTI ID:: 1507158

Journal Information:: Nano Letters, Journal Name: Nano Letters Journal Issue: 2 Vol. 19; ISSN 1530-6984

Publisher:: American Chemical SocietyCopyright Statement

Country of Publication:: United States

Language:: English

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