Electron-phonon coupling in EuAl4 under hydrostatic pressure

TL;DR

This study investigates how hydrostatic pressure affects electron-phonon coupling in EuAl4, revealing its role in charge-density wave formation and demonstrating pressure as a tuning parameter for charge order in quantum materials.

Contribution

It provides new experimental insights into pressure-dependent electron-phonon interactions in EuAl4, emphasizing their importance in charge-density wave phenomena.

Findings

EPC is renormalized and suppressed under pressure

Pressure influences the charge-density wave transition temperature

External pressure can tune charge ordering in EuAl4

Abstract

In the intermetallid rare-earth tetragonal EuAl4 system, competing itinerant exchange mechanisms lead to a complex magnetic phase diagram, featuring a centrosymmetric skyrmion lattice. Previous inelastic x-ray scattering (IXS) experiments revealed that the incommensurate charge-density wave (CDW) transition in EuAl4 (TCDW = 142 K) is driven by momentum-dependent electron-phonon coupling (EPC). We present the results of IXS under high hydrostatic pressure induced by diaond anvils and show how the EPC in EuAl4 is renormalized and suppressed in the material's temperature-pressure phase diagram. Our findings highlight the crucial role of momentum-dependent EPC in the formation of the CDW in EuAl4 and provide further insights into how external pressure can be used to tune charge ordering in quantum materials.