Microwave dielectric response of (Sr0.80Pb0.20)TiO3 based ferroelectric composites

This paper reports the results of measurements on the dielectric properties of strontium lead titanate ferroelectric composites (i.e. non-ferroelectric magnesium oxide, MgO, added to the Sr0.80Pb0.20TiO3, SPT, matrix) as a function of temperature over a wide frequency range from 0.05 to 2 GHz. The results showed that SPT–MgO composites have a strong dielectric dispersion (around 500 MHz) for the temperature range of 100–280 K. On the other hand, at room temperature a suppression of such relaxation was observed with low dielectric loss factors ∼5 × 10−4 over the entire range of frequency from 0.05 to 2 GHz. Such results evidence the potential use of SPT–MgO composites for room temperature tunable microwave applications.