Melting and transverse depinning of driven vortex lattices in the periodic pinning of Josephson junction arrays

VERONICA I. MARCONI; DANIEL DOMINGUEZ

PHYSICAL REVIEW B - CONDENSED MATTER AND MATERIALS PHYSICS

The American Physical Society

Año: 2001 vol. 63 p. 17450901 - 17450916

0163-1829

We study the non-equilibrium dynamical regimes  of a moving vortex lattice in the periodic pinning of a  Josephson junction array (JJA) for {it finitetemperatures} in the case of a fractional or submatching field.  We obtain a phase diagram for the current driven JJA  as a function of the driving current$I$ and temperature $T$.  We find that when the vortex lattice is driven by acurrent, the depinning transition at $T_p(I)$  and the melting transition at$T_M(I)$  become separated even for a field for which they coincide inequilibrium. We also distinguish between the depinning of the vortex lattice inthe direction of the current drive, and the {it transverse depinning} in thedirection perpendicular to the drive. The transverse depinning corresponds tothe onset of transverse  resistance in a moving vortex lattice at a giventemperature $T_{tr}$.  For driving currents  above the critical current  wefind that   the moving vortex lattice has first a transverse depinningtransition at low $T$,  and later a melting transition at a higher temperature,$T_{M}>T_{tr}$.