Doped high-T-c cuprate superconductors elucidated in the light of zeros and poles of the electronic Green's function

Article

关键词: HIGH-TEMPERATURE SUPERCONDUCTORS;    MONTE-CARLO METHOD;    MEAN-FIELD THEORY;    HUBBARD-MODEL;    SYSTEMS;    PHASE;    PSEUDOGAP;    STATE;    RENORMALIZATION;    DISPERSION;   

DOI  :  10.1103/PhysRevB.82.134505

来源: SCIE

【 摘 要 】

We study electronic structure of hole- and electron-doped Mott insulators in the two-dimensional Hubbard model to reach a unified picture for the normal state of cuprate high-T-c superconductors. By using a cluster extension of the dynamical mean-field theory, we demonstrate that structure of coexisting zeros and poles of the single-particle Green's function holds the key to understand Mott physics in the underdoped region. We show evidence for the emergence of non-Fermi-liquid phase caused by the topological quantum phase transition of Fermi surface by analyzing low-energy charge dynamics. The spectra calculated in a wide range of energy and momentum reproduce various anomalous properties observed in experiments for the high-T-c cuprates. Our results reveal that the pseudogap in hole-doped cuprates has a d-wavelike structure only below the Fermi level while it retains non-d-wave structure with a fully opened gap above the Fermi energy even in the nodal direction due to a zero surface extending over the entire Brillouin zone. In addition to the non-d-wave pseudogap, the present comprehensive identifications of the spectral asymmetry as to the Fermi energy, the Fermi arc, and the back-bending behavior of the dispersion, waterfall, and low-energy kink, in agreement with the experimental anomalies of the cuprates, do not support that these originate from (the precursors of) symmetry breakings such as the preformed pairing and the d-density-wave fluctuations, but support that they are direct consequences of the proximity to the Mott insulator. Several possible experiments are further proposed to prove or disprove our zero mechanism.

【 授权许可】

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