paper

The Effect of Pointlike Impurities on d_{x^2-y^2} Charge Density Waves in Cuprate Superconductors

arXiv:1502.03298 · doi:10.1103/PhysRevB.91.104509

Abstract

Many cuprate superconductors possess an unusual charge-ordered phase that is characterized by an approximate intra-unit cell form factor and a finite modulation wavevector $\bq^\ast$. We study the effects impurities on this charge ordered phase via a single-band model in which bond order is the analogue of charge order in the cuprates. Impurities are assumed to be pointlike and are treated within the self-consistent t-matrix approximation (SCTMA). We show that suppression of bond order by impurities occurs through the local disruption of the form factor near individual impurities. Unlike -wave superconductors, where the sensitivity of to impurities can be traced to a vanishing average of the order parameter over the Fermi surface, the response of bond order to impurities is dictated by a few Fermi surface "hotspots". The bond order transition temperature thus follows a different universal dependence on impurity concentration than does the superconducting . In particular, decreases more rapidly than with increasing when there is a nonzero Fermi surface curvature at the hotspots. Based on experimental evidence that the pseudogap is insensitive to Zn doping, we conclude that a direct connection between charge order and the pseudogap is unlikely. Furthermore, the enhancement of stripe correlations in the La-based cuprates by Zn doping is evidence that this charge order is also distinct from stripes.

References in corpus (20)

Cited by in corpus (1)