Crossover from Weak- to Strong-Coupling Superconductivity and to Normal State with Pseudogap
نویسنده
چکیده
For an electron gas with a δ-function attraction we investigate the crossover from weak-coupling to strong-coupling superconductivity near zero temperature as well as near the temperature T , at which the strong coupling produces a pseudogap in the energy spectrum due to the binding of electron pairs. We present curves for the behavior of the superconductive transition temperature, the gap formation temperature, and the gap size as a function of coupling strength and temperature, both in two and three dimensions. The results should be useful for interpreting experimental data in underdoped and optimally doped cuprates.
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