Enhanced s⁎-wave component of the superconducting gap in overdoped HTSC cuprates with orthorhombic distortion

Makarov, I.A., Ovchinnikov, S.G.// Physics Letters, Section A: General, Atomic and Solid State Physics//

https://doi.org/10.1016/j.physleta.2022.128226

In this work, the concentration and temperature dependence of the superconducting gap of the HTSC cuprate in the orthorhombic phase are obtained within the framework of the Hubbard model taking into account the exchange mechanism of pairing. To elucidate the reasons for the unexpectedly large $s^{⁎}$ -wave component of the superconducting gap in the overdoped regime, the electronic structure of low-energy excitations and the k-dependent contributions of pair states to the gap components were investigated. It is shown that the $s^{⁎}$ -wave component growth results from the shallowing of the electron pocket in the region of the $s^{⁎}$ -wave component maximum.