Spectra of the effects of magnetic birefringence and dichroism in magnetic colloids with different particle sizes

Abstract

Experimental studies of the spectral dependences of the effects of birefringence and dichroism in magnetic colloids with magnetite nanoparticles with an average size of 5.5 and 8 nm have been carried out. It is shown that the magnitude of the effects in a sample with larger particles is approximately two times greater at the same volume concentration. Possible reasons for this difference are analyzed, considering the polydispersity of the samples, as well as the possibility of the presence of magnetically hard and superparamagnetic particles in them. The calculations of the spectra of the effects of birefringence and dichroism showed good agreement with the experimental data.