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Critical Behaviour of Thermal Relaxation in Disordered Systems

C. D. Mukherjee·K. K. Bardhan
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Abstract

At a composition far above the percolation threshold, the resistance of a composite sample increases with time due to Joule heating as a constant current of sufficiently large value is passed through the sample. If the current is less than a certain breakdown current ($I_b$) the resistance eventually reaches a steady value with a characteristic relaxation time $τ_h$. The latter diverges with current $I$ as $τ_h \sim {(1-I^2/ {I_b}^2)}^{-z}$. The value of the exponent $z$ displays large fluctuations leading to unusual scaling of the relaxation time. Comparisions with behaviour of thermodynamic dynamic critical phenomena are made.

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C. D. Mukherjee, K. K. Bardhan. 2003-03-17. Critical Behaviour of Thermal Relaxation in Disordered Systems. https://arxiv.org/abs/cond-mat/0303313

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