Bcs-bose theory of the superconducuting coherence length
摘要
A root-mean square fermion pair radius, defined in terms of an appropriate BCS-Bose pair wave function in momentum space, is obtained analytically in one-and three-dimensions via complex plane integration. Results are compared with the familiar Pippard coherence length, in weak coupling (BCS regime), and with the size of an isolated pair in strong coupling (Bose regime). Inspite of their comparatively small magnitudes, empirical cuprate coherence length data seem to be consistent with a weakly-coupled description within the BCS-Bose picture.