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تسجيل مستخدم جديدPhase separation of superconducting phases in the Penson-Kolb-Hubbard model
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Konrad Jerzy Kapcia
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In this paper we determine the phase diagrams (for $T=0$ as well as $T>0$) of the Penson-Kolb-Hubbard model for two dimensional square lattice within Hartree-Fock mean-field theory focusing on investigation of superconducting phases and possibility of the occurrence of the phase separation. We obtain that the phase separation, which is a state of coexistence of two different superconducting phases (with $s$-wave and $eta$-wave symmetries), occurs in define range of the electron concentration. In addition, increasing temperature can change the symmetry of the superconducting order parameter (from $eta$-wave into $s$-wave). The system considered exhibits also an interesting multicritical behaviour including bicritical points.
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