Glassy aging with modified Kohlrausch-Williams-Watts form
- School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067 (India)
In this paper, we address the question of whether aging in the nonequilibrium glassy state is controlled by the equilibrium {alpha}-relaxation process, which occurs at temperatures above T{sub g}. Recently, Lunkenheimer et al. [Phys. Rev. Lett. 95, 055702 (2005)] proposed a model for the glassy aging data of dielectric relaxation using a modified Kohlrausch-Williams-Watts form exp[-(t{sub age}/{tau}{sub age}){sup {beta}{sub age}}]. The aging time t{sub age} dependence of the relaxation time {tau}{sub age} is defined by these authors through a functional relation involving the corresponding frequency {nu}(t{sub age})=1/(2{pi}{tau}{sub age}), but the stretching exponent {beta}{sub age} is the same as {beta}{sub {alpha}}, the {alpha}-relaxation stretching exponent. We present here an alternative functional form for {tau}{sub age}(t{sub age}) directly involving the relaxation time itself. The proposed model fits the data of Lunkenheimer et al. perfectly with a stretching exponent {beta}{sub age} different from {beta}{sub {alpha}}.
- OSTI ID:
- 21101957
- Journal Information:
- Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics (Print), Journal Name: Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics (Print) Journal Issue: 6 Vol. 76; ISSN 1539-3755
- Country of Publication:
- United States
- Language:
- English
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