Dominant in-plane symmetric elastoresistance in CsFe2As2

TL;DR

This study investigates the elastoresistance of CsFe2As2, revealing a dominant in-plane symmetric response linked to a coherence-incoherence crossover, with no evidence of divergent nematic susceptibility.

Contribution

It demonstrates the importance of neutralizing thermal expansion and provides new insights into the elastoresistance behavior related to coherence-incoherence crossover in CsFe2As2.

Findings

Large in-plane symmetric elastoresistance response

Weaker response in symmetry-breaking channels

No evidence for divergent nematic susceptibility

Abstract

We study the elastoresistance of the highly correlated material CsFe2As2 in all symmetry channels. Neutralizing its thermal expansion by means of a piezoelectric-based strain cell is demonstrated to be essential. The elastoresistance response in the in-plane symmetric channel is found to be large, while the response in the symmetry-breaking channels is weaker and provides no evidence for a divergent nematic susceptibility. Rather, our results can be interpreted naturally within the framework of a coherence-incoherence crossover, where the low-temperature coherent state is sensitively tuned by the in-plane atomic distances.