Dynamical charge density fluctuations pervading the phase diagram of a Cu-based high-Tc superconductor

TL;DR

This study reveals pervasive short-range dynamical charge density fluctuations in cuprate superconductors, persisting across a wide temperature range and doping levels, potentially influencing their anomalous normal-state properties.

Contribution

It uncovers the existence of dynamical charge density fluctuations in cuprates, extending understanding beyond static charge density waves.

Findings

Dynamical charge density fluctuations persist above pseudogap temperature T*

Fluctuations are characterized by energies of a few meV

They pervade a large area of the phase diagram

Abstract

Charge density waves are a common occurrence in all families of high critical temperature superconducting cuprates. Although consistently observed in the underdoped region of the phase diagram and at relatively low temperatures, it is still unclear to what extent they influence the unusual properties of these systems. Using resonant x-ray scattering we carefully determined the temperature dependence of charge density modulations in (Y,Nd)Ba$_2$Cu$_3$O$_{7-{\delta}}$ for three doping levels. We discovered short-range dynamical charge density fluctuations besides the previously known quasi-critical charge density waves. They persist up to well above the pseudogap temperature T*, are characterized by energies of few meV and pervade a large area of the phase diagram, so that they can play a key role in shaping the peculiar normal-state properties of cuprates.