Bulk electronic structure of the antiferromagnetic superconducting phase in ErNi2B2C

TL;DR

This study uses temperature-dependent laser-photoemission spectroscopy to explore how antiferromagnetism and superconductivity interact in ErNi2B2C, revealing unique bulk electronic structures and deviations from BCS theory.

Contribution

First experimental observation of the bulk electronic structure of the antiferromagnetic superconducting phase in ErNi2B2C using laser-photoemission spectroscopy.

Findings

Spectra at the superconducting phase are very broad.

Superconducting gap deviates from BCS prediction below TN.

Results align with theoretical models explaining AF SC interplay.

Abstract

We have performed temperature (T) - dependent laser-photoemission spectroscopy of antiferromagnetic (AF) superconductor ErNi2B2C to study the electronic-structure evolution reflecting the interplay between antiferromagnetism and superconductivity. The spectra at the superconducting (SC) phase show a very broad spectral shape. T-dependent SC gap shows a sudden deviation from the BCS prediction just below TN. This observation can be well explained by the theoretical model and thus represents characteristic bulk electronic structure of the AF SC phase for the first time.