INFLUENCE OF DEFECTS ON MAGNETIC CHARACTERISTICS OF FERRITE-GARNET FILMS

Abstract

This paper presents a study of the effect of volumetric (bulk) defects associated with the local mechanical damage and thermal laser action on the domain structure and magnetic characteristics of epitaxial bismuth-containing garnet-ferrite Bi:FG magnetic films. It was found that uniaxial Bi:FG films are resistant to bulk defects, the size of which does not exceed the width of the film domains. It is shown that the considered bulk film defects affect the process of the film magnetization, the form of the magnetization curves, the magnitude of the coercive force and the ratio of the displacement field to the coercive force. Effect of femtosecond laser pulses exposure with a power density of 800 J/cm^2 on the coercivity of film was found. The 4 - fold increase of the coercive field near a defect is discovered (from 0,33 Oe to 1,44 Oe).

Keywords

• magnetic films
• ferrite garnets
• bulk defects
• domain structure
• coercivity