Energy of curved vortices in layered superconductors

(Received 15 December 1991, accepted 7 January 1992)

Abstract
An exact expression for the London free energy of a curved vortex is used to calculate the energy of simple tilting vortex deformations (spiral and planar) in a layered super-conductor which are not assumed to be small in contrast to the usual harmonic approximation. It is shown that contrary to some recent calculations the straight vortex configuration is stable with respect to spiral deformation no matter how large its amplitude is. The results for the tilting moduli of the vortex lattice are also obtained for the case of vortices inclined with respect to the axis.