Electronic properties and surface states of CeRh$_{2}$As$_{2}$

Abstract

Locally noncentrosymmetric CeRh$_{2}$As$_{2}$ exhibits characteristic two-phase unconventional $H$--$T$ superconducting phase diagram. The transition from even- to odd-parity superconducting phase is supported by the P4/nmm crystal structure and it can be induced by the external magnetic field. Dual nature of the Ce $f$ electrons and competition between their itinerant and localized nature can be important for its physical proprieties. The existing electronic band structure in this material is still under debate. Energy scale occurring in the system can be important for adequate theoretical description of its supercomputing properties. In this paper, we discuss electronic band structure obtained from {\it ab initio} calculations. We analyze electronic surface states which can be compared with recently obtained angle-resolved photoemission spectroscopy measurement (ARPES). Additionally, we present the analyses of the hopping parameters obtained from the electronic band structure. The As-Rh layers are characterized by much more significant hopping parameters between atoms than these obtained for the Ce-Ce atoms. This suggests need of a revision of the tight binding model necessary for adequate description of the physical properties of CeRh$_{2}$As$_{2}$.