Theory for underdoped high-Tc superconductors: effects of phase fluctuations
نویسنده
چکیده
In underdoped cuprates, Tc is thought to be determined by Cooper pair phase fluctuations because of the small superfluid density ns. Experimentally, Tc is found to scale with ns. The fluctuation-exchange approximation (FLEX) in its standard form fails to predict this behavior of Tc since it does not include phase fluctuations. We therefore extend the FLEX to include them selfconsistently. We present results for Tc[ns, x]. PACS numbers: 74.72-h, 74.20.Mn, 74.25.Jb
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