Inhomogeneous Electronic Distribution in High-T_c Cuprates

Abstract

We theoretically investigate the doping evolution of the electronic state of high-T c cuprate on both sides of the half-filling on the basis of the three-dimensional three-band Hubbard model with a layered structure using the Hartree-Fock approximation. Once a small amount of holes or electrons are doped into the half-filled state, our model exhibits the charge-transfer insulator-to-metal transition along with a chemical potential jump. At the same time, the doped holes or electrons are inhomogeneously distributed, and they tend to form clusters in the vicinity of the half-filling. This suggests the possibility of microscopic phase separation with the separation between the metallic and the insulating regions.

Broad Linewidth of Antiferromagnetic Spin Wave due to Electron Correlation

“…Simultaneously, the coexistence within one CuO 2 plane has also been observed by NMR measurements 33 and theoretically studied [43][44][45] . In addition, the phase separation between AF and dSC states may also be possible 46 . Even though the magnetic excitations in these cases are not obvious, their situations are close to the present study.…”

Ground-state phase diagram of the three-band d-p model

“…The fundamental model of cuprate high-temperature superconductors is the electronic model for the CuO 2 plane including copper and oxygen atoms. This model is called the d-p model (or three-band Hubbard model) [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. It is certain that the electron correlation plays an important role in the d-p model since the on-site Coulomb interaction U d between d electrons is large.…”