Staggered Pairing Phenomenology for UPd_2Al_3 and UNi_2Al_3

TL;DR

This paper uses a staggered-pairing Ginzburg-Landau model to explain the differing superconducting phase diagrams of UPd_2Al_3 and UNi_2Al_3, predicting charge-density waves as experimental signatures.

Contribution

It extends the staggered-pairing phenomenology to UPd_2Al_3 and UNi_2Al_3, explaining their superconducting behaviors and predicting observable charge-density waves.

Findings

Different phase diagrams explained by staggered-pairing model

Charge-density waves predicted as experimental test

Two-component order parameter identified

Abstract

We apply the staggered-pairing Ginzburg-Landau phenomenology to describe superconductivity in UPd_2Al_3 and UNi_2Al_3. The phenomenology was applied successfully to UPt_3 so it explains why these materials have qualitatively different superconducting phase diagrams although they have the same point-group symmetry. UPd_2Al_3 and UNi_2Al_3 have a two-component superconducting order parameter transforming as an H-point irreducible representation of the space group. Staggered superconductivity can induce charge-density waves characterized by new Bragg peaks suggesting experimental tests of the phenomenology.