Electric Field Dependence of a Hydrogen Impurity Mode in SrTiO3

Abstract
The temperature and electric field dependence of a 3500-cm1 absorption band arising from hydrogen impurities in SrTiO3 crystals have been measured. The phase transition at 102°K from a cubic to a tetragonal structure as well as externally applied electric fields at low temperature cause a multitude of symmetrically different positions for the impurity. The corresponding frequency shifts can be correlated with the structural changes in the crystal and with the behavior of the low-frequency phonons.