Coexistence of two universal relaxations in the glassy freezing of a deuteron dipole glassY.-S. Choi and J.-J. Kim
Physics Department, Korea Advanced Institute of Science and Technology Taejon 305-701, Korea email@example.com
(Received 23 July 2003; accepted in final form 23 October 2003)
A deuteron dipole glass 1-x(ND 4) xD 2PO 4 (DRADP- x, x=0.47) was studied on glassy freezing by low-frequency dielectric measurements at low temperatures of slow dynamic freezing. A very broad distribution of relaxation times (relaxation frequencies) was observed to show an apparent crossover behavior from the relaxation time distributions with a long-time (low-frequency) tail to the distributions with a short-time (high-frequency) tail as temperature was lowered to below 40 . We show that this apparent crossover behavior may be originated by two competing relaxations in coexistence: one characterized by an Arrhenius law and the other by an inverse Arrhenius law temperature dependence, corresponding to the two slow-relaxation modes ( C<0 and C>0) of the dynamically correlated domains (DCDs) model of Chamberlin et al.
64.70.Pf - Glass transitions.
77.22.Gm - Dielectric loss and relaxation.
78.30.Ly - Disordered solids.
© EDP Sciences 2004