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Electronic Structure of La2-xSrxCuO4 in the Vicinity of the Superconductor-Insulator Transition

A. Ino·C. Kim·M. Nakamura·T. Yoshida·T. Mizokawa·Z. -X. Shen·A. Fujimori·T. Kakeshita·H. Eisaki·S. Uchida
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Abstract

We report on the result of angle-resolved photoemission (ARPES) study of La$_{2-x}$Sr$_x$CuO$_4$ (LSCO) from an optimally doped superconductor ($x=0.15$) to an antiferromagnetic insulator ($x=0$). Near the superconductor-insulator transition (SIT) $x\sim 0.05$, spectral weight is transferred with hole doping between two coexisting components, suggesting a microscopic inhomogeneity of the doped-hole distribution. For the underdoped LSCO ($x\leq 0.12$), the dispersive band crossing the Fermi level becomes invisible in the $(0,0)-(π,π)$ direction unlike Bi$_2$Sr$_2$CaCu$_2$O$_{8+y}$. These observations may be reconciled with the evolution of holes in the insulator into fluctuating stripes in the superconductor.

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A. Ino, C. Kim, M. Nakamura, T. Yoshida, T. Mizokawa, Z. -X. Shen, A. Fujimori, T. Kakeshita, H. Eisaki, S. Uchida. 2000-05-23. Electronic Structure of La2-xSrxCuO4 in the Vicinity of the Superconductor-Insulator Transition. https://doi.org/10.1103/physrevb.62.4137

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