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arXiv · 2102.12015

Spin texture in a bilayer high-temperature cuprate superconductor

Xiancong Lu·David Sénéchal
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Abstract

We investigate the possibility of spin texture in the bilayer cuprate superconductor $\rm Bi_2Sr_2CaCu_2O_{8+\delta}$ using cluster dynamical mean field theory (CDMFT). The one-band Hubbard model with a small interlayer hopping and a Rashba spin-orbit coupling is used to describe the material. The $d$-wave order parameter is not much affected by the presence of the Rashba coupling, but a small triplet component appears. We find a spin texture circulating in the same direction around $\mathbf{k}=(0,0)$ and $\mathbf{k}=(\pi,\pi)$ and stable against the superconducting phase. The amplitude of the spin structure, however, is strongly affected by the pseudogap phenomenon, more so than the spectral function itself.

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Xiancong Lu, David Sénéchal. 2021-02-24. Spin texture in a bilayer high-temperature cuprate superconductor. https://doi.org/10.1103/physrevb.104.024502

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