Dielectric abnormal relaxation in condensed matter(Session I : Cross-Disciplinary Physics, The 1st Tohwa University International Meeting on Statistical Physics Theories, Experiments and Computer Simulations)

Abstract

It has been shown by many experimental data of polymers that the dielectric response function is of a stretched exponential, φ(t)=exp「-(t/τ^*)^<κ_β>」. The parameter β_κ is indicated to express a measure of the molecular interaction by the coupling model. Experimental data on β_κ support this. However deviation of the experimental complex permittivity from that calculated is common for polymers. The stretched exponential function explained the complex permittivity only in a frequency range log f/f_m&le;1.5 The deviation is in many cases independent of the frequency. No satisfactorily explanation has been given to this phenomenon. Below conventional glass transition temperature a relaxation peak of Debye type can be seen in an ultra-low frequency region.