TEMPERATURE-DEPENDENCE OF THE SUPERCONDUCTING CONDENSATE AND GAP IN BI2SR2CA1CU2O8+X

Using high energy resolution angle-resolved photoemission, we have mea sured both the superconducting gap and the photoemission superconducti ng condensate spectral area of Bi2Sr2Ca1Cu1O8+x as a function of tempe rature in two different locations of the Brillouin zone. We found that the size of superconducting gap along the Gamma - X direction decreas es to values indistinguishable from zero for which the gap retains vir tually full value along the Gamma - (M) over bar direction. The increa sed gap anisotropy with increasing temperature is in contrast to what happens for conventional anisotropic superconductors such as lead.