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The Fermi surface of underdoped high-T_c superconducting cuprates

Xi Dai·Zhao-bin Su·Lu Yu
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Abstract

The coexistence of $π$-flux state and d-wave RVB state is considered in this paper within the slave boson approach. A critical value of doping concentration $δ_c$ is found, below which the coexisting $π$-flux and d-wave RVB state is favored in energy. The pseudo Fermi surface of spinons and the physical electron spectral function are calculated. A clear Fermi-level crossing is found along the (0,0) to ($π$, $π$) direction, but no such crossing is detected along the ($π$, 0) to ($π$, $π$) direction. Also, an energy gap of d-wave symmetry appears at the Fermi level in our calculation. The above results are in agreement with the angle-resolved photoemission experiments which indicate at a d-wave pseudo-gap and a half-pocket-like Fermi surface in underdoped cuprates.

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Xi Dai, Zhao-bin Su, Lu Yu. 1997-05-06. The Fermi surface of underdoped high-T_c superconducting cuprates. https://doi.org/10.1016/s0921-4534(97)00918-0

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