paper

Density Waves Cause Sub-Gap Structures but no Pseudogap in Superconducting Cuprates

arXiv:1610.01109 · doi:10.1103/PhysRevB.95.054518

Abstract

In scanning tunneling microscopy (STM) conductance curves, the superconducting gap of cuprates is sometimes accompanied by small sub-gap structures at very low energy. This was documented early on near vortex cores and later at zero magnetic field. Using mean-field toy models of coexisting d-wave superconductivity (SC), \emph{d}-form factor density wave (FF-DW), and extended s-wave pair density wave (PDW), we find agreement with this phenomenon, with PDW playing a critical role. We explore the high variability of the gap structure with changes in band structure and density wave (DW) wave vector, thus explaining why sub-gap structures may not be a universal feature in cuprates. In the absence of nesting, non-superconducting results never show signs of pseudogap, even for large density waves magnitudes, therefore reinforcing the idea of a distinct origin for the pseudogap, beyond mean-field theory. Therefore, we also briefly consider the effect of DWs on a pre-existing pseudogap.

13 pages, 8 figures

References in corpus (25)

Cited by in corpus (1)