Effect of Phase Fluctuations on the Low-Temperature
Penetration Depth of High-Tc Superconductors
Eric Roddick and David Stroud, Department of Physics,
The Ohio State University, Columbus, Ohio 43210
We describe a simple model to estimate the effects of order parameter phase
fluctuations on the penetration depth $\lambda(T)$ of high-T$_c$
superconductors. When treated classically,
such fluctuations are found to produce a
linear temperature-dependence of $\lambda(T)$, which may be
comparable to the experimentally observed magnitude. This dependence
persists when the combined effects of charging interactions and dissipation
are included in the model. Hence, such a dependence may not be a unique
signature of a superconductor with line nodes at the Fermi surface.
PACS numbers: 74.25.Nf, 74.25.Bt, 74.40.+k, 74.72.Bk