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Nodal metallic behavior of lightly-doped La$_{2-x}$Sr$_x$CuO$_4$

T. Yoshida·X. J. Zhou·T. Sasagawa·W. L. Yang·P. V. Bogdanov·A. Lanzara·Z. Hussain·T. Mizokawa·A. Fujimori·H. Eisaki·Z. -X. Shen·T. Kakeshita·S. Uchida
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Abstract

Lightly-doped La$_{2-x}$Sr$_x$CuO$_4$ in the so-called "insulating" spin-glass/diagonal-stripe phase has been studied by angle-resolved photoemission spectroscopy. A quasi-particle (QP) peak crossing the Fermi level has been observed in the node direction of the d-wave superconducting gap, forming an "arc" of Fermi surface consistent with the recently observed metallic transport behavior at high temperatures of lightly-doped materials. The spectral weight of the nodal QP smoothly increases with hole doping, corresponding to the $n \sim x$ behavior of the carrier number in the underdoped and lightly-doped regions.

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T. Yoshida, X. J. Zhou, T. Sasagawa, W. L. Yang, P. V. Bogdanov, A. Lanzara, Z. Hussain, T. Mizokawa, A. Fujimori, H. Eisaki, Z. -X. Shen, T. Kakeshita, S. Uchida. 2003-07-11. Nodal metallic behavior of lightly-doped La$_{2-x}$Sr$_x$CuO$_4$. https://doi.org/10.1103/physrevlett.91.027001

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