Relationship between condensation energy and dimensionality of Bi-2212 superconductor

The condensation energy which determines the pinning strength is estimated from the pinning property of the columnar defects for Bi-2212 superconductor in various doped states of oxygen. It is found that the condensation energy increases drastically with decreasing anisotropy parameter. In the low temperature region the condensation energy density of Bi-2212 increases abnormally with decreasing temperature and this suggests a drastic change in the superconductivity in the block layer