Low-frequency Raman response near the Ising-nematic quantum critical point: A memory-matrix approach
Low-frequency Raman response near the Ising-nematic quantum critical point: A memory-matrix approach
Recent Raman scattering experiments have revealed a quasielastic peak in ${\mathrm{FeSe}}_{1\ensuremath{-}\mathrm{x}}{\mathrm{S}}_{\mathrm{x}}$ near an Ising-nematic quantum critical point (QCP) [Zhang et al., PNAS 118, 20 (2021)]. Notably, the peak occurs at subtemperature frequencies, and softens as ${T}^{\ensuremath{\alpha}}$ when temperature is decreased toward the QCP, with $\ensuremath{\alpha}>1$. This temperature dependence is inconsistent …