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Theory for underdoped high-T_c superconductors: effects of phase fluctuations

F. Schaefer·C. Timm·D. Manske·K. H. Bennemann
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Abstract

In underdoped cuprates, T_c is thought to be determined by Cooper pair phase fluctuations because of the small superfluid density n_s. Experimentally, T_c is found to scale with n_s. The fluctuation-exchange approximation (FLEX) in its standard form fails to predict this behavior of T_c since it does not include phase fluctuations. We therefore extend the FLEX to include them selfconsistently. We present results for T_c[n_s,x], where x is the doping.

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F. Schaefer, C. Timm, D. Manske, K. H. Bennemann. 1999-08-06. Theory for underdoped high-T_c superconductors: effects of phase fluctuations. https://arxiv.org/abs/cond-mat/9907345

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