Magnetic Polarons in EuO

Abstract

The existence of spin‐polarized complexes or magnetic polarons in magnetic semiconductors has been suggested theoretically some time ago, but up to now there is little experimental evidence of this phenomenon. With this in view, electron paramagnetic resonance is investigated (g‐factor and linewidth temperature coefficient) and also several other electrical and magnetic parameters of EuO‐based magnetic semiconductors with various donor concentrations (oxygen vacancies or Gd3+ ions substituting Eu2+ ions). The results of the investigation show that in a limited region of donor concentrations and temperatures there occurs a localization of charge carriers which may be attributed to the formation of magnetic polarons. Copyright © 1988 WILEY‐VCH Verlag GmbH & Co. KGaA