Bose-Einstein to BCS crossover picture for high-T-c cuprates

Combining (1) the universal correlations between T-c and n(s)/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 T-c to the superfluid volume density n(s) in all these cases indicate importance of Bose condensation.