High quality pure YAlO3 crystal with dimension of Φ 30 x 50 mm2 was grown by Czochralski technique. UV irradiation and air annealing bring additional absorption in the region 200–800nm. The absorption spectra of perfect YAlO3 and YAlO3 containing cation vacancy (aluminium vacancy and yttrium vacancy) were calculated using density functional theory code CASTEP. Comparison of the simulated absorption spectra with the experimental absorption spectra of YAlO3 after UV irradiation and air annealing treatments showed that cation vacancies were responsible for part of the coloration on YAlO3 crystal.

Color Center of YAlO3 with Cation Vacancies. J.Chen, G.Zhao, D.Cao, S.Zhou: Current Applied Physics, 2010, 10[2], 468-70