Metallic normal state of Y1Ba2Cu3O(7-delta)
Flux flow was studied over an entire temperature range down to T approximately 2% of T(c) by using intense pulsed current densities to overcome flux-vortex pinning. The resistivity at high vortex velocities is proportional to B and roughly follows rho approximately rho(n)B/H(c2), with a prefactor of order unity. Contrary to some speculation, rho(n) saturates to a finite residual value as T-->0, indicating a metallic (rho-->finite) rather than insulating (rho-->infinity) normal state, and the vortex dissipation continues to be conventional as T-->0.
Kunchur
MN
Department of Physics and Astronomy, University of South Carolina, Columbia, South Carolina 29208, USA.
Ivlev
BI
Christen
DK
Phillips
JM