Phonon anomalies within the polar charge density wave phase of the structurally chiral superconductor Mo$_3$Al$_2$C

Shangfei Wu; Xianghan Xu; Fei-Ting Huang; Turan Birol; Sang-Wook Cheong; Girsh Blumberg

doi:10.1103/nkx2-6qyr

paper

Phonon anomalies within the polar charge density wave phase of the structurally chiral superconductor Mo $_{3}$ Al $_{2}$ C

arXiv:2502.19826 · doi:10.1103/nkx2-6qyr

Abstract

We employ polarization-resolved Raman spectroscopy to study the lattice dynamics of the polar charge density wave phase of the superconductor Mo $_{3}$ Al $_{2}$ C with structural chirality. We show the phononic signatures of the charge density wave transition at $T^{*}$ = 155\,K in Mo $_{3}$ Al $_{2}$ C. The detailed temperature dependence of these phonon modes' frequency, half width at half maximum, and integrated area below $T^{*}$ reveal anomalies at an intermediate temperature $T^{'} \sim$ 100\,K, especially for the low-energy modes at 130 and 180\,\cm-1. We discuss the origin of these phonon anomalies within the polar charge density wave phase of Mo $_{3}$ Al $_{2}$ C.

10 pages, 6 figures. The supplemental materials are included. Journal version

Phonon anomalies within the polar charge density wave phase of the structurally chiral superconductor Mo3​Al2​C

Abstract

Phonon anomalies within the polar charge density wave phase of the structurally chiral superconductor Mo $_{3}$ Al $_{2}$ C