Temperature dependence of a magnetoresistance effect in the films of ferromagnetic semiconductors based on oxides of rare-earth elements

A temperature dependence of a positive magnetoresistance effect for films o f certain oxides of rare-earth elements (Gd, Eu, and a Eu-Sm solid solution ) close to the Curie temperature was considered and analyzed. It was demons trated that the temperature dependence of the effect and the effect sign an d magnitude are determined by the dependence of a magnetic moment for a mag netic cluster on both an external magnetic field strength and film paramete rs. These are the spin of the magnetic ion, exchange energy, defect density , etc. (C) 2001 MAIK "Nauka/ Interperiodica".