The relaxation of the specific heat to its equilibrium value is investigated numerically for the three-dimensional Coulomb glass at very low temperatures. For that we first obtain an almost complete set of low-energy many-particle states. The dynamic of the sample is mapped to the graph formed by the relevant transitions between these states, that means by transitions with rates larger than the inverse of the observation time. A two-steps decay for the process of relaxation is found. The long time relaxation step follow a stretched exponential function, $f(t)=f_0\exp\left[-(t/\tau)^\beta\right]$, with the exponent $\beta$ increasing with the temperature. The relaxation time diverges as an Arrhenius law when $T\rightarrow 0$.

Ritorno all'elenco dei poster