The ac conductivity studies for Cu2O–Bi2O3 glassy system

The ac conductivity for the Cu2O–Bi2O3 glassy system has been measured in the temperature range −150 to 180°C. The ac conductivity was found to be sensitive to frequency, temperature and Cu content. The ac conductivity (σ) of the glassy system at constant isotherms increases with frequency ω, and σ(ω) was found to be proportional to ωs. The obtained values of the density of states using the Elliott model were of the order of 1016, which is in good agreement with the values found in the literature. The temperature dependence of the ac conductivity shows a slow rate at low temperature and high rate at high temperature. This has been attributed to electron hopping mechanism at first and then to the band-to-band transition mechanism. Several theoretical models describing the ac conductivity of glassy systems were discussed. Among these different models, the Elliot model was found to be most appropriate for the present glassy system.