Chemical Potential Shift in Overdoped and UnderdopedLa2−xSrxCuO4

A. Ino, T. Mizokawa, A. Fujimori, K. Tamasaku, H. Eisaki, S. Uchida, T. Kimura, T. Sasagawa, K. Kishio
1997 Physical Review Letters  
The downward shift of the electron chemical potential m with hole doping in La 22x Sr x CuO 4 has been deduced from the shifts of photoemission and inverse-photoemission spectra. While the shift is large (ϳ1.5 eV͞hole) in overdoped samples, it is suppressed (,0.2 eV͞hole) in underdoped samples, implying a divergent charge susceptibility near the metal-insulator transition. In the overdoped regime, the m and the electronic specific heat coefficient g are consistently explained within
more » ... theory, whereas the same analysis gives unphysical results in the underdoped regime, indicating the breakdown of the Fermi-liquid picture in the underdoped regime. [S0031-9007(97)04058-1]
doi:10.1103/physrevlett.79.2101 fatcat:h64jvkur3vho5atrjtebbedapy