“…With the substitution of yttrium with bismuth or rare earth elements such as cerium, it is possible to enhance the FE with only small changes of magnetic moment [10,11], while the garnet maintains its important property as an electrical insulator. The influence of the substitution of bismuth on the magneto-optic properties has been investigated intensively [12][13][14][15], while for cerium only the FE has been studied in bulk [16][17][18] and to a lesser extent for thin films [19][20][21][22][23], However, studies have not been carried out on the magneto-optic Kerr effect (MOKE) in Ce∶YIG, which is relevant for magneto-optic readout applications that are based on reflection geometry. As the MOKE in YIG is known to be small for wavelengths in the red and nearinfrared spectral range, used for optical communications, Ce∶YIG thin films are potentially promising, but the MOKE in Ce∶YIG needs to be characterized in this wavelength range.…”