AC CONDUCTION IN SEMICONDUCTING CUO-BI2O3-P2O5 GLASSES

The first measurements are reported for the AC conductivity (real and imaginary parts) of the semiconducting CuO-Bi2O3-P 2O5 glasses in the frequency range 102-10 5 Hz and in the temperature range 80-4000 K. The experimental results have been analysed in the light of various theoretical models proposed for amorphous semiconductors such as quantum mechanical tunnelling and classical hopping over the barrier of a charge carrier. The analysis shows that the correlated barrier-hopping model predicts the correct temperature and frequency dependence of the AC conductivity and its frequency exponent. This model provides reasonable values of the maximum barrier height and characteristic relaxation time.