SHEAR INSTABILITIES OF A VORTEX LATTICE IN LAYERED SUPERCONDUCTORS

We study possible structures of a vortex lattice in highly layered superconductors (ξc≈s) with the magnetic field parallel to the layers. When the magnetic field is large and the vortex lattice is dense enough, the shear modulus is exponentially small, and one can expect the vortex lattice to melt in between the layers and a vortex smectic to be formed. For low magnetic fields the vortices are far apart, and a triangular array becomes unstable with respect to the formation of several new types of vortex lattices. © 1990 Plenum Publishing Corporation.