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

doi:10.1103/PhysRevB.62.4137

paper

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

arXiv:cond-mat/9902048 · doi:10.1103/PhysRevB.62.4137

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 $(0, 0) - (I ¨ , I ¨ )$ 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.

5 pages, 6 EPS figures, use RevTex, to be published in Phys. Rev. B