Spectroscopic evidences of quantum critical charge fluctuations in cuprates

TL;DR

This paper investigates how charge fluctuations near quantum critical points affect the optical properties of cuprates, revealing anomalous behaviors and the influence of lattice coupling on scaling.

Contribution

It provides spectroscopic evidence linking quantum critical charge fluctuations to optical conductivity anomalies in cuprates, highlighting the role of lattice interactions.

Findings

Charge-ordering collective modes cause anomalous optical absorption.

Lattice coupling introduces a non-universal energy scale.

Scaling violations occur at low temperatures due to lattice effects.

Abstract

We calculate the optical conductivity in a clean system of quasiparticles coupled to charge-ordering collective modes. The absorption induced by these modes may produce an anomalous frequency and temperature dependence of low-energy optical absorption in some cuprates. However, the coupling with lattice degrees of freedom introduces a non-universal energy scale leading to scaling violation in low-temperature optical conductivity.