Weakly first-order phase transitions: Epsilon expansion vs. numerical simulation

David Mukamel, S. Krinsky, Per Bak

Alain H. Billoire, R. Lacaze, André Morel

Marcelo Gleiser

The dynamics of weak vs strong first order phase transitions is investigated numerically for (2 + 1)-dimensional scalar field models. It is argued that the change from a weak to a strong transition is itself a (second order) phase transition, with the order parameter being the equilibrium fractional population difference between the two phases at the critical temperature, and the control parameter being the coefficient of the cubic coupling in the free-energy density. The critical point is identified, and a power law controlling the relaxation dynamics at this point is obtained. Possible applications are briefly discussed.

N. Tetradis

Ian D. Lawrie

Recent Monte Carlo simulations by Dasgupta and Halperin (1981) of a lattice model for superconductivity indicate a continuous transition, but do not rule out a first-order transition for sufficiently small electric charge. The author shows conversely that earlier arguments for a first-order transition in the continuum model fail when the charge exceeds a certain maximum value, which he calculates at first order of the epsilon expansion.

Alain H. Billoire