Magnetic and magneto-optical investigation of CoCrTa and CoCrPt films

Abstract

Magnetic and magneto-optic measurements (polar Kerr rotation and ellipticity) have been taken for a series of CoCrTa and CoCrPt single layer films with different thicknesses. The magnetic layers were rf sputter deposited onto constant thickness titanium layers on glass substrates at room temperature. Experimental data were obtained at two different wavelengths, i.e., 825 and 670 nm. The perpendicular coercivity Hc measured at the two wavelengths increased with film thickness. Conversely, the lower thickness showed the highest θk and this decreased as the thickness increases. The opposite trend has been noticed for CoCrPt films. There is no difference in the grain size from transmission electron microscopy examination. The results of the investigation are presented in the context of the need for magneto-optic material to be optimized for short wavelength applications in the future.