Odd Parity and Line Nodes in Heavy Fermion Superconductors

TL;DR

This paper challenges existing group theory constraints on odd parity superconducting order parameters, showing exceptions on specific lattice faces that could impact understanding of heavy fermion superconductors like UPt3.

Contribution

It demonstrates that odd parity order parameters can have line nodes on certain lattice faces, contrary to previous group theory predictions, with implications for heavy fermion superconductors.

Findings

Three odd parity representations vanish on the $k_z = rac{\pi}{c}$ zone face.

Exceptions to the no-line-node rule are identified in hexagonal lattices.

Potential relevance to the superconductor UPt3.

Abstract

Group theory arguments have demonstrated that a general odd parity order parameter cannot have line nodes in the presence of spin-orbit coupling. In this paper, it is shown that these arguments do not hold on the $k_z = \pi/c$ zone face of a hexagonal close packed lattice. In particular, three of the six odd parity representations vanish identically on this face. This has potential relevance to the heavy fermion superconductor $UPt_3$.