Quantitative Theory of Triplet Pairing in the Unconventional Superconductor LaNiGa$_2$
Abstract
The exceptionally low-symmetry crystal structures of the time-reversal symmetry breaking superconductors LaNiC and LaNiGa lead to an internally-antisymmetric non-unitary triplet (INT) state as the only possibility compatible with experiments. We argue that this state has a distinct signature: a double-peak structure in the Density of States (DOS) which resolves in the spin channel in a particular way. We construct a detailed model of LaNiGa capturing its electronic band structure and magnetic properties ab initio. The pairing mechanism is described via a single adjustable parameter. The latter is fixed by the critical temperature allowing parameter-free predictions. We compute the electronic specific heat and find excellent agreement with experiment. The size of the ordered moment in the superconducting state is compatible with zero-field muon spin relaxation experiments and the predicted spin-resolved DOS suggests the spin-splitting is within the reach of present experimental technology.
Keywords
Cite
@article{arxiv.1912.08160,
title = {Quantitative Theory of Triplet Pairing in the Unconventional Superconductor LaNiGa$_2$},
author = {Sudeep Kumar Ghosh and Gábor Csire and Philip Whittlesea and James F. Annett and Martin Gradhand and Balázs Újfalussy and Jorge Quintanilla},
journal= {arXiv preprint arXiv:1912.08160},
year = {2020}
}
Comments
Accepted in PRB as a rapid communication