High-temperature infrared reflectivity of yttria-stabilized hafnia single crystals

Infrared reflectivity spectra of cubic yttria-stabilized hafnia were measured in the frequency range 30–5000 cm−1 at temperatures from 300 to 1100 K. A heavily damped oscillator has been observed in the far infrared, its parameters being essentially constant in the whole temperature range. This term is attributed to vibrations of clusters of defects, in accord with previous studies on other fluorite-type ionic conductors.