Doping-dependent evolution of the electronic structure of La2-xSrxCuO4 in the superconducting and metallic phases

A. Ino, C. Kim, M. Nakamura, Takashi Mizokawa, T. Mizokawa, A. Fujimori, Z. X. Shen, T. Kakeshita, H. Eisaki, S. Uchida

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294 引用 (Scopus)

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The electronic structure of the La2-xSrxCuO4 (LSCO) system has been studied by angle-resolved photo-emission spectroscopy (ARPES). We report on the evolution of the Fermi surface, the superconducting gap, and the band dispersion around the extended saddle point k = (π,0) with hole doping in the superconducting and metallic phases. As hole concentration x decreases, the flat band at (π,0) moves from above the Fermi level (EF) for x>0.2 to below EF for x<0.2, and is further lowered down to x = 0.05. From the leading-edge shift of ARPES spectra, the magnitude of the superconducting gap around (π,0) is found to monotonically increase as x decreases from x = 0.30 down to x = 0.05 even though Tc decreases in the underdoped region, and the superconducting gap appears to smoothly evolve into the normal-state gap at x = 0.05. It is shown that the energy scales characterizing these low-energy structures have similar doping dependences. For the heavily overdoped sample (x = 0.30), the band dispersion and the ARPES spectral line shape are analyzed using a simple phenomenological self-energy form, and the electronic effective mass enhancement factor m*/mb≃2 has been found. As the hole concentration decreases, an incoherent component that cannot be described within the simple self-energy analysis grows intense in the high-energy tail of the ARPES peak. Some unusual features of the electronic structure observed for the underdoped region (x≤0.10) are consistent with numerical works on the stripe model.

元の言語English
記事番号094504
ページ(範囲)945041-9450411
ページ数8505371
ジャーナルPhysical Review B - Condensed Matter and Materials Physics
65
発行部数9
出版物ステータスPublished - 2002 3 1
外部発表Yes

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ASJC Scopus subject areas

  • Condensed Matter Physics

これを引用

Ino, A., Kim, C., Nakamura, M., Mizokawa, T., Mizokawa, T., Fujimori, A., Shen, Z. X., Kakeshita, T., Eisaki, H., & Uchida, S. (2002). Doping-dependent evolution of the electronic structure of La2-xSrxCuO4 in the superconducting and metallic phases. Physical Review B - Condensed Matter and Materials Physics, 65(9), 945041-9450411. [094504].