Tilt modulus and angle-dependent flux lattice melting in the lowest Landaulevel approximation

For a clean high-T-c superconductor, we analyze the Lawrence-Doniach free e nergy in a tilted magnetic field within the lowest Landau level approximati on. The free energy maps onto that of a strictly c-axis field, but with a r educed interlayer coupling. We use this result to calculate the tilt modulu s C-44 Of a vortex lattice and vortex liquid. The vortex contribution to C- 44 can be expressed in terms of the squared c-axis Josephson plasmon freque ncy omega (2)(pl). The transverse component of the field has very little ef fect on the position of the melting curve.