Dissipation mechanism above the current threshold in Josephson junction chains

Abstract

We present measurements on one-dimensional Josephson junction arrays formed by a chain of SQUID loops in the regime where $E_J/E_c\simeq 1$. We observe a blockaded zero current branch for small bias voltages. Above a certain voltage $V_{\mathrm{sw}}$ the $I$-$V$ characteristics changes discontinuously to a dissipative branch characterized by a flux dependent conductance. Three of four samples show a pronounced hysteresis for a forward and backward voltage sweep. We observe a periodic field dependence of the conductance above $V_{\mathrm{sw}}$ which can be described with $P(E)$ theory for cooper-pairs and therefore gives evidence of viscous dynamics of Cooper pair transport through the array.

11 pages, 6 figures

Cited by in corpus (1)

• One-dimensional Josephson junction arrays: Lifting the Coulomb blockade by depinning