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arXiv · 1002.2972

Evolution of the electronic structure from the insulator to the superconductor in Bi2Sr2-xLax(Ca,Y)Cu2O8+d

K. Tanaka·T. Yoshida·K. M. Shen·D. H. Lu·W. S. Lee·H. Yagi·A. Fujimori·Z. -X. Shen·Risdiana·T. Fujii·I. Terasaki
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Abstract

La-doped and Y-doped Bi2Sr2CaCu2O8+d (Bi2212) compounds Bi2Sr2-xLax(Ca,Y)Cu2O8+d, which range from the insulator to the deeply underdoped superconductor, have been studied by angle-resolved photoemission spectroscopy. We have observed that the lower Hubbard band (LHB) of the parent insulator is gradually shifted upward with doping without significantly changing the band dispersions, which implies a downward shift of the chemical potential with hole doping. This behaviour is analogous to Bi2Sr2-xLaxCuO6+d (Bi2201) and Ca2-xNaxCuO2Cl2 (Na-CCOC) but is different from La2-xSrxCuO4 (LSCO), where the LHB stays well below the chemical potential and does not move while its intensity quickly diminishes in the underdoped region.

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K. Tanaka, T. Yoshida, K. M. Shen, D. H. Lu, W. S. Lee, H. Yagi, A. Fujimori, Z. -X. Shen, Risdiana, T. Fujii, I. Terasaki. 2010-02-15. Evolution of the electronic structure from the insulator to the superconductor in Bi2Sr2-xLax(Ca,Y)Cu2O8+d. https://doi.org/10.1103/physrevb.81.125115

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