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

G. Alvarez·H. Fort
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Abstract

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

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G. Alvarez, H. Fort. 2000-10-09. The Effect of Large Amplitude Fluctuations in the Ginzburg-Landau Phase Transition. https://doi.org/10.1103/physrevb.64.092506

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