Large spin splittings due to the orbital degree of freedom and spin textures in a ferroelectric nitride perovskite
Résumé
First-principles simulations are conducted to predict that ferroelectric nitride perovskite LaWN 3 not only exhibits large spin splittings (2.7 eV Å) but also possesses unique spin textures for some of its conduction levels. Such spin splittings around the and L points cannot be interpreted as a typical mixture of Rashba or Dresselhaus configurations but rather require the development of four-band k • p models with high-order terms. We further identify that, for some bands, spin splittings can be greatly contributed by the pure orbital degree of freedom (PODF), a unique character of our four-band Hamiltonian compared to the traditional two-band version. The concept of PODF-enhanced spin splittings paves a way for designing materials with large spin splittings. Moreover, the energy levels possessing such large splittings and complex spin textures can be brought close to the conduction-band minimum by applying epitaxial strain.
| Origine | Fichiers éditeurs autorisés sur une archive ouverte |
|---|