The Effect of Large Amplitude Fluctuations in the Ginzburg-Landau Phase Transition

Abstract

The lattice Ginzburg-Landau model in d=3 and d=2 is simulated, for different values of the coherence length $\xi$ in units of the lattice spacing $a$, using a Monte Carlo method. The energy, specific heat, vortex density $v$, helicity modulus ${\Gamma }_{\mu }$ and mean square amplitude are measured to map the phase diagram on the plane $T-\xi$. When amplitude fluctuations, controlled by the parameter $\xi$, become large ($\xi \sim 1$) a proliferation of vortex excitations occurs changing the phase transition from continuous to first order.

4 pages, 5 postscript (eps) figures

References in corpus (3)

• Two Experimental Tests of the Halperin-Lubensky-Ma Effect at the Nematic-Smectic-A Phase Transition
• First Order Transition in the Ginzburg-Landau Model
• Phase Transitions Driven by Vortices in 2D Superfluids and Superconductors: From Kosterlitz-Thouless to 1st Order

Cited by in corpus (2)

• Single-Particle Density of States of a Superconductor with a Spatially Varying Gap and Phase Fluctuations
• Nature of Phase Transitions in a Generalized Complex |psi|^4 Model