Stretched exponential relaxation in a diffusive lattice model.
We studied the single dimer dynamics in a lattice diffusive model as a function of particle density in the high densification regime. The mean square displacement is found to be subdiffusive both in one and two dimensions. The spatial dependence of the self-part of the van Hove correlation function displays as a function of r a single peak and signals a dramatic slow down of the system for high density. The self-intermediate scattering function is fitted to the Kohlrausch-Williams-Watts law. The exponent beta extracted from the fits is density independent while the relaxation time tau follows a scaling law with an exponent 2.5.
Fusco
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Dipartimento di Fisica, Università Roma Tre, and Istituto Nazionale per la Fisica della Materia, Unità di Ricerca Roma Tre, Via della Vasca Navale 84, I-00146 Roma, Italy.
Gallo
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Petri
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A
Rovere
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