A universal distribution function of relaxation in amorphous materials

Abstract A universal distribution function of the relaxation time is proposed for the non-exponential relaxation process in amorphous materials. This function contains the usual exponential decay, the extended exponential decay (Williams-Watts decay) and the power law decay as the special case of the function. Photoluminescence and dielectric relaxation observed in the amorphous materials is well reproduced by this function on the time dependence of the relaxation process and its Fourier transform in the wide range of time and frequency for many kinds of amorphous materials.