Pyroelectric Effect Induced by the Built-in Field in the p-n Junction of the Quantum Paraelectric PbTe: Experimental Study

We report here the first observation of a pyroelectric effect in a non-polar semiconductor. This effect originates in the temperature dependent electric dipole of the p-n junction. The junction was illuminated by a chopped CO2 laser beam, and periodic and single-pulse pyroelectric signals were observed and measured as a function of temperature, reverse bias voltage and chopper frequency. The measured pyroelectric coefficient is about 10^(-3) microC/cm2K in the region of 40-80 K. The theoretical model describes quantitatively all experimental features. The time evolution of the temperature inside the junction region was reconstructed.