The photoinduced Ti³centre in SrTiO₃

Abstract

We report the results of an electron spin resonance study of Ti3+ centres in SrTiO3 single crystals. The Ti3+ centres are created in perturbed regular Ti4+ sites by trapping a photoelectron from the conduction band after ultraviolet irradiation of the sample at low temperature (T < 180 K). The centres are stable below ∼180 K. To our knowledge this is the first observation of such Ti3+ defects in a SrTiO3 lattice.