Phonon softening in Lu(PtPd)In close to a zero-temperature structural instability

Gruner, T.*; Lucas, S.*; Geibel, C.*; 金子 耕士; 筒井 智嗣*; Schmalzl, K.*; Stockert, O.*

Physical Review B, 106(11), p.115142_1 - 115142_6, 2022/09

https://doi.org/10.1103/PhysRevB.106.115142

The disappearance of a charge-density-wave (CDW) transition in Lu(PtPd)In is thought to be closely linked to a maximum of the superconducting transition temperature in the system. We studied the superstructure and the phonon softening in Lu(PtPd)In by means of neutron and high-resolution inelastic X-ray scattering. A full phonon softening at = (0.5, 0.5, 0) with the appearance of superstructure peaks could be clearly identified. The large tail of the superstructure intensity above the CDW transition indicates the importance of critical fluctuations.