Temperature-dependent gap equations and their solutions in the SU(4) model of high-temperature superconductivity

Abstract

Temperature-dependent gap equations in the SU(4) model of high-Tc superconductivity are derived and analytical solutions are obtained. Based on these solutions, a generic gap diagram describing the features of energy gaps as functions of doping P is presented and a phase diagram illustrating the phase structure as a function of temperature T and doping P is sketched. A special doping point P_q occurs naturally in the solutions that separates two phases at temperature T = 0: a pure superconducting phase on one side (P > P_q) and a phase with superconductivity strongly suppressed by antiferromagnetism on the other (P < P_q). We interpret P_q as a quantum phase transition point. Moreover, the pairing gap is found to have two solutions for P < P_q: a small gap that is associated with competition between superconductivity and antiferromagnetism and is responsible for the ground state superconductivity, and a large gap without antiferromagnetic suppression that corresponds to a collective excited state. A pseudogap appears in the solutions that terminates at P_q and originates from the competition between d-wave superconductivity and antiferromagnetism. Nevertheless, this conclusion does not contradict the preformed pair picture conceptually if the preformed pairs are generally defined as any pairs formed before pairing condensation.

arXiv comment23 pages, 5 color figures

References in corpus (18)

• Angle-resolved photoemission spectroscopy of the cuprate superconductors
• The pseudogap in high-temperature superconductors: an experimental survey
• The doping dependence of T* - what is the real high-Tc phase diagram?
• Exactly solvable Richardson-Gaudin models for many-body quantum systems
• Algebraic models of hadron structure: I. Nonstrange baryons
• SO(5) Theory of Antiferromagnetism and Superconductivity
• Theory of the Resonant Neutron Scattering of High $T_c$ Superconductors
• The superfluid density in cuprate high-Tc superconductors - a new paradigm
• Interlayer tunneling spectroscopy of Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+\delta }$: a look from inside on the doping phase diagram of high $T_c$ superconductors
• An SU(4) Model of High-Temperature Superconductivity and Antiferromagnetism
• Spin-Charge Separation is the Key to the High T_c Cuprates
• Kondo effect in systems with dynamical symmetries
• Quantum Protectorates in the Cuprate Superconductors
• SO(5) as a Critical Dynamical Symmetry in the SU(4) Model of High-Temperature Superconductivity
• Phase diagram and dynamics of the projected SO(5)-symmetric model of high-$T_c$ superconductivity
• Stripes, pseudogaps, and SO(6) in the cuprate superconductors
• Theory of Coexistence of Superconductivity and Ferroelectricity : A Dynamical Symmetry Model
• Mott Insulators, No-Double-Occupancy, and Non-Abelian Superconductivity

Cited by in corpus (4)

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• A Unified Description of Cuprate and Iron Arsenide Superconductors
• k-dependent SU(4) model of high-temperature superconductivity and its coherent-state solutions
• Fermion dynamical symmetry and strongly-correlated electrons: a comprehensive model of high-temperature superconductivity