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arXiv · 0704.1486

Nodal/Antinodal Dichotomy and the Two Gaps of a Superconducting Doped Mott Insulator

M. Civelli·M. Capone·A. Georges·K. Haule·O. Parcollet·T. D. Stanescu·G. Kotliar
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Abstract

We study the superconducting state of the hole-doped two-dimensional Hubbard model using Cellular Dynamical Mean Field Theory, with the Lanczos method as impurity solver. In the under-doped regime, we find a natural decomposition of the one-particle (photoemission) energy-gap into two components. The gap in the nodal regions, stemming from the anomalous self-energy, decreases with decreasing doping. The antinodal gap has an additional contribution from the normal component of the self-energy, inherited from the normal-state pseudogap, and it increases as the Mott insulating phase is approached.

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M. Civelli, M. Capone, A. Georges, K. Haule, O. Parcollet, T. D. Stanescu, G. Kotliar. 2008-02-04. Nodal/Antinodal Dichotomy and the Two Gaps of a Superconducting Doped Mott Insulator. https://doi.org/10.1103/physrevlett.100.046402

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