We have studied the in-plane paraconductivity in single crystals of YBa2Cu3O7 with exceptionally sharp transitions. For temperatures greater than 1 K above the transition temperature Tc, we find good qualitative and some quantitative agreement with the two-dimensional Aslamazov-Larkin theory. The jump to zero resistance occurs in a narrow interval of less than 0.5 K. Our data are inconsistent with the Lawrence-Doniach expression for crossover from two to three dimensions.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics