Abstract
By means of density functional theory calculations, we predict that several two-dimensional binary monolayers, where and atoms belong to group IV or III-V, are ferroelectric. Dipoles arise from the buckled structure, where the and ions are located on the sites of a bipartite corrugated honeycomb lattice with trigonal symmetry. We discuss the emerging valley-dependent properties and the coupling of spin and valley physics, which arise from the loss of inversion symmetry, and explore the interplay between ferroelectricity and Rashba spin-splitting phenomena. We show that valley-related properties originate mainly from the binary nature of monolayers, while the Rashba spin-texture developing around valleys is fully controllable and switchable by reversing the ferroelectric polarization.
- Received 2 January 2015
- Revised 11 February 2015
DOI:https://doi.org/10.1103/PhysRevB.91.161401
©2015 American Physical Society