Nonequilibrium enhancement of high-temperature superconductivity in a 3D model of cuprates

TL;DR

This paper models how optical excitation can transiently enhance high-temperature superconductivity in cuprates by suppressing competing charge order through inter-plane tunneling effects in a 3D $t-J-V$ model.

Contribution

It extends the cuprate model to three dimensions and demonstrates how optical pumping can enhance superconductivity by suppressing charge order.

Findings

Optical pump suppresses charge density wave order.

Superconductivity is transiently enhanced during pumping.

Inter-plane tunneling plays a key role in the effect.

Abstract

Recent experiments in the cuprates have seen evidence of a transient superconducting state upon optical excitation polarized along the c-axis [R. Mankowsky et al., Nature 516, 71 (2014)]. Motivated by these experiments we propose an extension of the single-layer $t-J-V$ model of cuprates to three dimensions in order to study the effects of inter-plane tunneling on the competition between superconductivity and bond density wave order. We find that an optical pump can suppress the charge order and simultaneously enhance superconductivity, due to the inherent competition between the two. We also provide an intuitive picture of the physical mechanism underlying this effect. Furthermore, based on a simple Floquet theory we estimate the magnitude of the enhancement.