Coexistence of $\Theta_{II}$-loop-current order with checkerboard d-wave CDW/PDW order in a hot-spot model for cuprate superconductors

TL;DR

This paper shows that in a model for cuprate superconductors, the $ heta_{II}$-loop-current order coexists with bidirectional d-wave CDW/PDW orders but suppresses unidirectional stripe orders, aligning with recent experimental findings.

Contribution

It demonstrates, using a saddle-point approximation, that the $ heta_{II}$-loop-current order coexists with bidirectional CDW/PDW orders and inhibits unidirectional stripe orders in a hot-spot model for cuprates.

Findings

Loop-current order coexists with bidirectional CDW/PDW

Loop-current order suppresses unidirectional stripe order

Results align with recent x-ray experiments on YBCO

Abstract

We investigate the strong influence of the $\Theta_{II}$-loop-current order on both unidirectional and bidirectional d-wave charge-density-wave/pair-density-wave (CDW/PDW) composite orders along axial momenta $(\pm Q_0,0)$ and $(0,\pm Q_0)$ that emerge in an effective hot spot model departing from the three-band Emery model relevant to the phenomenology of the cuprate superconductors. This study is motivated by the compelling evidence that the $\Theta_{II}$-loop-current order described by this model may explain groundbreaking experiments such as spin-polarized neutron scattering performed in these materials. Here, we demonstrate, within a saddle-point approximation, that the $\Theta_{II}$-loop-current order clearly coexists with bidirectional (i.e. checkerboard) d-wave CDW and PDW orders along axial momenta, but is visibly detrimental to the unidirectional (i.e. stripe) case. This result has potentially far-reaching implications for the physics of the cuprates and agrees well with very recent x-ray experiments on YBCO that indicate that at higher dopings the CDW order has indeed a tendency to be bidirectional.