Off-Equilibrium Dynamics of 1+1 dimensional Directed Polymer in Random Media
نویسنده
چکیده
The relaxational dynamics of 1+1 dimensional directed polymer in random potential is studied by Monte Carlo simulations. A series of temperature quench experiments is performed changing waiting times tw. Clear crossover from quasi-equilibrium behavior (t ≪ tw) to off-equilibrium behavior (t ≫ tw) appears in the dynamical overlap function whose scaling properties are very similar to those found in the 3 dimensional spin-glass model. In the t ≫ tw part, the fluctuation dissipation theorem of the 1st kind which relates the response function to the tilt field with the conjugate correlation function, is found broken. These aging effects are brought about by the very slow growth of quasi-equilibrium domain driven by successive loop-excitations of various sizes, which form complex network structures. 02.50.Ey, 74.60.Ge, 75.10.Nr. Typeset using REVTEX 1
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