Tunable giant Rashba-type spin splitting in PtSe2/MoSe2 heterostructure
Abstract
We report a giant Rashba-type spin splitting in two-dimensional heterostructure PtSe2/MoSe2 with first-principles calculations. We obtain a large value of spin splitting energy 110 meV at the momentum offset k0 = 0.23 Å-1 around the Γ point, arising from the emerging strong interfacial spin-orbital coupling induced by the hybridization between PtSe2 and MoSe2. Moreover, we find that the band dispersion close to the valence band maximum around the Γ point can be well approximated by the generalized Rashba Hamiltonian H ( k | | ) = - /ℏ 2 k| | 2 2 m + c k | | + α R σ → . ( k → | | × z → ) . It is found that the generalized Rashba constant η R = c + α R in PtSe2/MoSe2 is as large as 1.3 eVṡÅ and, importantly, ηR can be effectively tuned by biaxial strain and external out-of-plane electrical field, presenting a potential application for the spin field-effect transistor (SFET). In addition, with the spin-valley physics at K / K ' points in monolayer MoSe2, we propose a promising model for SFETs with optovalleytronic spin injection based on a PtSe2/MoSe2 heterostructure.
- Publication:
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Applied Physics Letters
- Pub Date:
- November 2019
- DOI:
- 10.1063/1.5125303
- arXiv:
- arXiv:1908.06689
- Bibcode:
- 2019ApPhL.115t3501X
- Keywords:
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- Condensed Matter - Materials Science
- E-Print:
- Major changes have been made to the manuscript, including proposing a generalized Rashba Hamiltonian, modifying Fig. 3, changing the discussion of proposed SFET device, adding results to the supplementary materials, and so on