FRACTAL ANALYSIS OF THE MAZE-LIKE DOMAIN STRUCTURE OF FERRITE-GARNET FILMS IN THE PROCESS OF MAGNETIZATION

Abstract

In this work, using a set of experimental techniques and specialized software, magnetic bismuth-containing ferrite-garnet films grown on gadolinium-gallium garnet substrates are investigated. The limiting magnetic hysteresis loops are obtained by the method of optical magnetometry for defective and defect-free areas of bismuth-containing ferrite-garnet films. It was found that, far from defects, the loop exhibits a non-coercive behavior within the error limits. For the case of magnetization reversal, a coercive state with Hcl~1 Oe appears near the defect. For different sections of the limiting magnetic hysteresis loop, the fractal dimension is determined. The obtained values are in the range of DL=1,35÷1,46 for an arbitrary section of the film and DL=1,37÷1,54 for a section with defects. Typical morphological characteristics of the surface of a bismuth-containing ferrite-garnet film have been determined. The results obtained make it possible to predict the relationship between the value of magnetization and the value of fractal dimension for epitaxial bismuth-containing magnetic films of iron garnet.

Keywords

• magnetic films
• ferrite garnets
• bulk defects
• domain structure
• coercivity
• fractal dimension
• nanorelief