Melting of Flux Lines in an Alternating Parallel Current

Abstract

We use a Langevin equation to examine the dynamics and fluctuations of a flux line (FL) in the presence of an {\it alternating longitudinal current} $J_{\parallel }(\omega )$. The magnus and dissipative forces are equated to those resulting from line tension, confinement in a harmonic cage by neighboring FLs, parallel current, and noise. The resulting mean-square FL fluctuations are calculated {\it exactly}, and a Lindemann criterion is then used to obtain a nonequilibrium `phase diagram' as a function of the magnitude and frequency of $J_{\parallel }(\omega )$. For zero frequency, the melting temperature of the mixed phase (a lattice, or the putative "Bose" or "Bragg Glass") vanishes at a limiting current. However, for any finite frequency, there is a non-zero melting temperature.

5 pages, 1 figure

References in corpus (1)

• Nonequilibrium dislocation dynamics and instability of driven vortex lattices in two dimensions

Cited by in corpus (2)

• Pinning and Sliding of Driven Elastic Systems: from Domain Walls to Charge Density Waves
• Instability and Fluctuations of Flux Lines with Point Impurities in a Parallel Current