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arXiv · cond-mat/9812031

Phase Diagram of a Superconducting and Antiferromagnetic System with SO(5) Symmetry

X. Hu·T. Koyama·M. Tachiki
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Abstract

Temperature vs. chemical-potential phase diagrams of an SO(5) model for high-(T_c) cuprates are calculated by Monte Carlo simulation. There is a bicritical point where the second-order antiferromagnetism (AF) and superconductivity transition lines merge tangentially into a first-order line, and the SO(5) symmetry is achieved. In an external magnetic field, the AF ordering is first order in the region where the first-order melting line of flux lattice joins in. There is a tricritical point on the AF transition line from which the AF ordering becomes second order.

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X. Hu, T. Koyama, M. Tachiki. 1998-12-02. Phase Diagram of a Superconducting and Antiferromagnetic System with SO(5) Symmetry. https://doi.org/10.1103/physrevlett.82.2568

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