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

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 $T^{\ast }$ = 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 $T^{\ast }$ reveal anomalies at an intermediate temperature $T^{\prime }\sim$ 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

References in corpus (8)

• Coupled Ferroelectricity and Superconductivity in Bilayer $T_d$-MoTe${}_2$
• Critical enhancement of thermopower in a chemically tuned polar semimetal MoTe${}_2$
• Charge-order-induced ferroelectricity in LaVO${}_3$/SrVO${}_3$ superlattices
• Polar Metals Taxonomy for Materials Classification and Discovery
• Lattice dynamics, crystal-field excitations and quadrupolar fluctuations of YbRu${}_2$Ge${}_2$
• Emergent charge ordering in near half doped Na${}_{0.46}$CoO${}_2$
• Electron-lattice coupling contributions to polarization switching in charge-order-induced ferroelectrics
• Polar charge density wave in a superconductor with crystallographic chirality

Cited by in corpus (1)

• Kondo-Peierls transition with nonsymmorphic zone boundary gap formation