Flow equation approach to the linear response theory of superconductors

Article

关键词: HIGH-TEMPERATURE SUPERCONDUCTORS;    RENORMALIZATION-GROUP APPROACH;    UNDERDOPED BI2SR2CACU2O8+DELTA;    COOPER PAIRS;    PHASE;    FLUCTUATIONS;    HAMILTONIANS;    STATE;    SYSTEMS;   

DOI  :  10.1103/PhysRevB.84.174520

来源: SCIE

【 摘 要 】

We apply the flow equation method for studying the current-current response function of electron systems with the pairing instability. To illustrate the specific scheme in which the flow equation procedure determines the two-particle Green's functions, we reproduce the standard response kernel of the BCS superconductor. We next generalize this nonperturbative treatment considering the pairing field fluctuations. Our study indicates that the residual diamagnetic behavior detected above the transition temperature in the cuprate superconductors can originate from the noncondensed preformed pairs.

【 授权许可】

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