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Transition metal ions such as Mn 2+ , Fe 2+ , or Co 2+ provide an interesting alternative to rare earth dopants in optically active glasses. In terms of their magneto-optical properties, they are not yet very well exploited. Here, we report on the effect of Mn 2+ on Faraday rotation in a metaphosphate glass matrix along the join Mn x Sr 1-x (PO 3 ) 2 with x = 0...1. Mn 2+ shows small optical extinction in the visible spectral range and, compared to other transition metal ions, a high effective magnetic moment. At high Mn-levels, however, the magneto-optical activity of Mn 2+ is strongly quenched due to ionic clustering. The magnetic properties of the heavily Mn 2+ -loaded phosphate matrix are dominated by a superexchange interaction in the Mn 2+ -O-Mn 2+ bridge with antiparallel spin alignment between Mn 2+ and O 2species. The apparent paramagnetic potential of Mn 2+ species can therefore not be exploited at room temperature.

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Amorphous wide bandgap semiconductor thin films of the pseudobinary compound (SiC)1-x(AlN)x were grown by radio frequency dual magnetron sputtering on CaF2, MgO and glass substrates. We performed isochronical annealing steps up to 500°C. The optical bandgap is determined for each composition from spectroscopic transmission measurement in two different ways: according to Tauc and using the (αhν)2 plot. The dependence of the optical bandgap on the composition x can be described by Vegard’s empirical law for alloys.