Electrical conductivity and dielectric properties of bismuth aluminate, Bi12.47Al0.53O19.5 （BAO）, were investigated in the frequency range from 1 Hz to 1 MHz in the temperature range from 420 K to 5 K. In the temper...Electrical conductivity and dielectric properties of bismuth aluminate, Bi12.47Al0.53O19.5 （BAO）, were investigated in the frequency range from 1 Hz to 1 MHz in the temperature range from 420 K to 5 K. In the temperature range from 360 K to 220 K the real part of the complex ac electrical conductivity and dielectric constant follow the universal dielectric response （UDR）, being typical for hopping or tunneling of localized charge carriers. A detailed analysis of the temperature dependence of the UDR parameter s in terms of the theoretical model for tunneling of small polarons revealed that below 360 K this mechanism governs the charge transport in this material. The characteristic parameters for polarons, W∞, ιo, and ι0 were determined.展开更多
文摘Electrical conductivity and dielectric properties of bismuth aluminate, Bi12.47Al0.53O19.5 （BAO）, were investigated in the frequency range from 1 Hz to 1 MHz in the temperature range from 420 K to 5 K. In the temperature range from 360 K to 220 K the real part of the complex ac electrical conductivity and dielectric constant follow the universal dielectric response （UDR）, being typical for hopping or tunneling of localized charge carriers. A detailed analysis of the temperature dependence of the UDR parameter s in terms of the theoretical model for tunneling of small polarons revealed that below 360 K this mechanism governs the charge transport in this material. The characteristic parameters for polarons, W∞, ιo, and ι0 were determined.
