Bose-Einstein to BCS Crossover Picture for High-Tc Cuprates
نویسنده
چکیده
Combining (1) the universal correlations between Tc and ns/m ∗ (superconducting carrier density / effective mass) and (2) the pseudo-gap behavior in the underdoped region, we obtain a picture to describe superconductivity in cuprate systems in evolution from Bose-Einstein to BCS condensation. Overdoped and Zn-substituted cuprate systems show signatures of reduced superfluid density in a microscopic phase separation. Scaling of Tc to the superfluid volume density ns in all these cases indicate importance of Bose condensation.
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