Complex optical constants and magneto-optic Kerr effect of Co/Al/Co sandwiches

The effective complex optical constants and the magneto-optical Kerr effect (MOKE) were measured for sputtered Co/Al/Co sandwiches. The four effective dielectric tensor elements were evaluated. It was found that the Kerr rotation and the Kerr ellipticity depend on both the real and imaginary parts of the effective off-diagonal element of the dielectric tensor and the variation of the complex MOKE with changing the thickness of the Al spacer was due not only to the variation of the effective off-diagonal element but also to the variation of the effective optical constants. Large variations of the effective optical constants of the sandwiches were observed.