Glassy dynamics, aging and temperature-induced avalanches in interface pinning at finite temperatures

We study numerically the out-of-equilibrium dynamics of interfaces at finite temperatures when driven well below the zero-temperature depinning threshold. We go further than previous analysis by including the most relevant non-equilibrium correction to the elastic Hamiltonian. We find that the relaxation dynamics towards the steady state shows glassy behaviour, aging and violation of the fluctuation-dissipation theorem. The interface roughness exponent α ≈ 0.7 is found to be robust to temperature changes. We also study the instantaneous velocity signal in the low-temperature regime and find long-range temporal correlations. We argue that 1/f-noise arises from the merging of local temperature-induced avalanches of depinning events.