Doping evolution of Zhang-Rice singlet spectral weight: A comprehensive examination by x-ray absorption spectroscopy

作者:Chen Y J*; Jiang M G; Luo C W; Lin J Y; Wu K H; Lee J M; Chen J M; Kuo Y K; Juang J Y; Mou Chung Yu
来源:Physical Review B, 2013, 88(13): 134525.
DOI:10.1103/PhysRevB.88.134525

摘要

The total spectral weight S of the emergent low-energy quasiparticles in high-temperature superconductors (HTSCs) is explored by x-ray absorption spectroscopy. In order to examine the applicability of the Hubbard model, regimes that cover from zero doping to overdoping are investigated. In contrast to results of mean-field theory, we found that S deviates from linear dependence on the doping level p. The slope of S versus p changes continuously throughout the whole doping range with no sign of saturation up to p = 0.23. Therefore, the picture of the Zhang-Rice singlet remains intact within the most prominent doping regimes of HTSCs.