Eur. Phys. J. Special Topics 228, 631–641 (2019)
https://doi.org/10.1140/epjst/e2019-800194-2

Regular Article

Spin–orbit coupling effects on the electronic properties of the pressure-induced superconductor CrAs

¹ Dipartimento di Fisica “E.R. Caianiello”, Università degli Studi di Salerno, 84084 Fisciano (SA), Italy
² International Research Centre Magtop, Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, 02668 Warsaw, Poland
³ Consiglio Nazionale delle Ricerche CNR-SPIN, UOS Salerno, 84084 Fisciano (Salerno), Italy
⁴ Unità CNISM di Salerno, Università degli Studi di Salerno, 84084 Fisciano (SA), Italy

^a e-mail: gcuono@unisa.it

Received: 8 November 2018
Published online: 3 July 2019

Abstract

We present the effects of spin-orbit coupling on the low-energy bands and Fermi surface of the recently discovered pressure-induced superconductor CrAs. We apply the Löwdin down-folding procedure to a tight-binding hamiltonian that includes the intrinsic spin-orbit interaction, originating from the Cr 3d electrons as well as from As 4p ones. Our results indicate that As contributions have negligible effects, whereas the modifications to the band structure and the Fermi surface can be mainly ascribed to the Cr contribution. We show that the inclusion of the spin-orbit interaction allows for a selective removal of the band degeneracy due to the crystal symmetries, along specific high symmetry lines. Such release of the band degeneracy naturally determines a reconstruction of the Fermi surface, including the possibility of changing the number of pockets.