Abstract
Comparing photoemission measurements on Bi2212 with penetration depth data, we show that a description of the nodal excitations of the -wave superconducting state in terms of noninteracting quasiparticles is inadequate, and we estimate the magnitude and doping dependence of the Landau interaction parameter which renormalizes the linear contribution to the superfluid density. Furthermore, although consistent with -wave symmetry, the gap with underdoping cannot be fit by the simple form, which suggests an increasing importance of long range interactions as the insulator is approached.
- Received 23 December 1998
DOI:https://doi.org/10.1103/PhysRevLett.83.840
©1999 American Physical Society