Marko MILIVOJEVIĆ. Superconducting pairings and topology in Ising superconductors with Rashba spin-orbit coupling: The example of NbSe2
Marko MILIVOJEVIĆ, Institute of Informatics, Slovak Academy of Sciences, Slovakia and
Faculty of Physics, University of Belgrade, Serbia
Le résumé :
The NbSe2 monolayer with Rashba spin-orbit coupling represents a paradigmatic example of an Ising superconductor on a substrate. Using a single-band model and symmetry analysis, we present general superconducting pairing functions beyond the nearest-neighbour approximation, uncovering new types of gap functions, including the nodal singlet gap function and the triplet non-unitary pairing function that breaks time-reversal symmetry.
Our classification, based on the irreducible representations of the C3v symmetry, reveals the intriguing possibility of singlet-triplet mixing within the superconducting pairing function. By exploring the most general form of this mixing, we uncover a spectrum of topological phases that can emerge in the system, alongside their dependence on Fermi-level doping. Our findings highlight that topological superconductivity can not only exist, but also be adjusted by changing the Fermi level. This suggests a potential method for externally controlling the topological states in these systems.
J. Haniš, M. Milivojević, and M. Gmitra, Physical Review B 110, 104502 (2024).
Z. Tajkov, J. Haniš, M. Milivojević, and M. Gmitra, in preparation