Stochastic production of kink-antikink pairs in the presence of an oscillating background

Abstract

We numerically investigate the production of kink-antikink pairs in a $(1+1)$-dimensional ${\ensuremath{\varphi}}^{4}$ field theory subject to white noise and periodic driving. The twin effects of noise and periodic driving acting in conjunction lead to considerable enhancement in the kink density compared to the thermal equilibrium value, for low dissipation coefficients and for a specific range of frequencies of the oscillating background. The dependence of the kink density on the temperature of the heat bath, the amplitude of the oscillating background and value of the dissipation coefficient is also investigated. An interesting feature of our result is that kink-antikink production occurs even though the system always remains in the broken symmetry phase.