Abstract
Infrared absorption spectra of the ErCrO3 crystal in the region of $$f{-} f$$ transitions in the Er3+ ion are recorded for the first time. An analysis of high-resolution temperature-dependent spectra reveals a step at $$T{\kern 1pt} ' = 47$$ K on the temperature dependences of the characteristics of spectral lines, in addition to the features at temperatures of magnetic ordering TN = 133 K and spin-reorientation transition $${{T}_{{{\text{SR}}}}} = 9.3{\kern 1pt} $$ K. This feature can be associated with either a previously unknown phase transition or with local changes in the crystal structure. The shape of the lines at liquid helium temperatures indicates the presence of additional positions for Er3+ ions in the ErCrO3 crystal. Presumably, these are positions near uncontrolled impurities that enter the crystal during its growth by the solution–melt method and form regions with a distorted structure responsible for the occurrence of polarization.
Subject
Physics and Astronomy (miscellaneous)