Modulation of pairing interaction in Bi2Sr2CaCu2O8+delta by an O dopant: A density functional theory study

Article

关键词: HIGH-TC SUPERCONDUCTIVITY;    VALENCE BOND STATE;   

DOI  :  10.1103/PhysRevB.82.054514

来源: SCIE

【 摘 要 】

Scanning tunneling spectroscopy measurements on the high-temperature superconductor Bi2Sr2CaCu2O8+delta have reported an enhanced spectral gap in the neighborhood of O dopant atoms. We calculate, within density functional theory (DFT), the change in electronic structure due to such a dopant. We then construct and discuss the validity of several tight-binding (TB) fits to the DFT bands with and without an O dopant. With the doping-modulated TB parameters, we finally evaluate the spin susceptibility and pairing interaction within spin-fluctuation theory. The d-wave pairing eigenvalues are enhanced above the pure system without O dopant, supporting the picture of enhanced local pairing around such a defect.

【 授权许可】

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