Mechanism of unconventional superconductivity induced by skyrmion excitations in two-dimensional strongly correlated electron systems

Article

关键词: QUANTUM HEISENBERG-ANTIFERROMAGNET;    HIGH-TEMPERATURE SUPERCONDUCTIVITY;    HIGH-TC SUPERCONDUCTORS;    VALENCE-BOND STATE;    X-RAY ABSORPTION;    D-P MODEL;    2 DIMENSIONS;    CUO2 PLANES;    ANISOTROPIC SUPEREXCHANGE;    TRANSITION-TEMPERATURE;   

DOI  :  10.1103/PhysRevB.65.064513

来源: SCIE

【 摘 要 】

We propose a mechanism of unconventional superconductivity in two-dimensional strongly correlated electron systems. We consider a two-dimensional Kondo lattice system or double exchange system with spin-orbit coupling arising from buckling of the plane. We show that a Chern-Simons term is induced for a gauge field describing the phase fluctuations of the localized spins. Through the induced Chern-Simons term, carriers behave like skyrmion excitations that lead to a destruction mechanism of magnetic long-range order by carrier doping. After magnetic long-range order is destroyed by carrier doping, the Chern-Simons term plays a dominant role and the attractive interaction between skyrmions leads to unconventional superconductivity. For the case of the ferromagnetic interaction between the localized spins, the symmetry of the Cooper pair is p wave (p(x) +/- ip(y)). For the case of the antiferromagnetic interaction between the localized spins, the symmetry of the Cooper pair is d wave (d(x2-y2)). Applications to various systems are discussed, in particular to the high-T-c cuprates.

【 授权许可】

Free