Coherent vibrations in percolative oil-resin systems: A Bose condensation effect observed by the technique of thermostimulated currents

摘要

The analysis of thermostimulated currents by the fractional polarization procedure is used to understand percolative behaviors in conductor-insulator-like oil-resin mixtures. On the fundamental side oil-poor systems are particularly attractive. They offer for the first time the opportunity to apply a pure Debye-like dielectric treatment of the quasi-elastic dipolar relaxation since the involved dipoles are independent, associated with spatially separated bounded clusters. An unusual compensation phenomenon is observed in the sense that first it does not describe hierarchically correlated motions and secondly it is related to the conducting phase but exhibits characteristics of the insulating phase. This compensation phenomenon is interpreted within the framework of Fr0hlich's approach of relaxation processes in biological materials, as significative of a coherent vibration resulting from Bose condensation effects. On the practical side, the surveillance of this compensation phenomenon appears to be a new way to follow the coalescence of conducting bounded clusters with aging.