Large spin splitting in the conduction band of transition metal dichalcogenide monolayers

K. Kośmider, J. W. González, and J. Fernández-Rossier
Phys. Rev. B 88, 245436 – Published 23 December 2013

Abstract

We study the conduction band spin splitting that arises in transition metal dichalcogenide (TMD) semiconductor monolayers such as MoS2, MoSe2, WS2, and WSe2 due to the combination of spin-orbit coupling and lack of inversion symmetry. Two types of calculation are done. First, density functional theory (DFT) calculations based on plane waves that yield large splittings, between 3 and 30 meV. Second, we derive a tight-binding model that permits to address the atomic origin of the splitting. The basis set of the model is provided by the maximally localized Wannier orbitals, obtained from the DFT calculation, and formed by 11 atomiclike orbitals corresponding to d and p orbitals of the transition metal (W, Mo) and chalcogenide (S, Se) atoms respectively. In the resulting Hamiltonian, we can independently change the atomic spin-orbit coupling constant of the two atomic species at the unit cell, which permits to analyze their contribution to the spin splitting at the high symmetry points. We find that—in contrast to the valence band—both atoms give comparable contributions to the conduction band splittings. Given that these materials are most often n-doped, our findings are important for developments in TMD spintronics.

  • Figure
  • Figure
  • Figure
  • Figure
  • Received 5 November 2013

DOI:https://doi.org/10.1103/PhysRevB.88.245436

©2013 American Physical Society

Authors & Affiliations

K. Kośmider, J. W. González*, and J. Fernández-Rossier

  • International Iberian Nanotechnology Laboratory (INL), Av. Mestre José Veiga, 4715-330 Braga, Portugal

  • *Current address: Centro de Física de Materiales (CSIC-UPV/EHU)-Material Physics Center (MPC), Paseo Manuel de Lardizábal 5, 20018, San Sebastián, Spain.
  • On leave from Departamento de Física Aplicada, Universidad de Alicante, Spain.

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 88, Iss. 24 — 15 December 2013

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review B

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×