LAYERED SUPERCONDUCTORS .2. MELTING OF PARALLEL-FLUX LATTICE

A system of superconducting layers with Josephson coupling J between neighboring layers is studied in the presence of a magnetic field parallel to the layers. A sequence of ''l phases'' is produced where the induced flux lines are l layers apart. An l phase is solved by an equivalent fermion problem and its melting temperature T(m)(l) is found. When J is not too small, there is a range l(min) < l < l(max) for which two-dimensional phases are possible and l(min)=8-10. These results account for the current-voltage relation of the form V approximately I(a(T)) as observed in many of the high-T(c) superconductors.