Numerical study of fermi surface evolution in cuprates using one-band hubbard model

A Numerical calculation of the Fermi Surface (FS) evolution in cuprate using the oneband Hubbard model by the matrix diagonalization method has been done. This work focusses on the study of the evolution of the FS in the cuprate material, namely Bi2Sr2CaCu2O8+δ, numerically by introducing a specific order parameter in the Hubbard model matrix. In this study, we confirm two evolution types of the FS of Bi2Sr2CaCu2O8+δ as an experimental result. Firstly, the evolution of the antibonding FS topology from the electron-like to the hole-like is generated by the order parameter that has a form of tdcos(kx).cos(ky) where td is the order parameter coefficient that corresponds to the hopping parameter of the atomic neighbor long-range interaction and kx,ky is the normalized momenta coordinate of the first Brillouin zone. On the contrary, the order parameter that has a form of tdcos(2kx)+cos(2ky)] generates the evolution of the FS from the hole-like topology to the electron-like topology. Secondly, the anisotropic evolution of the FS can be described by an extended d-wave order parameter which generating either the V-shape or U-shape type of the energy gap. © 2020 Trans Tech Publications Ltd, Switzerland.