Magnetooptical properties of Y3Fe5-xScxO12Garnets

Magnetooptical spectra Faraday Rotation (F.R.), Magnetic circular dichroism MCD and magnetoreflection (\frac{\DeltaR}{R}) of Y3Fe5-xScxO12garnets have been investigated in the range 15000-21000 cm^-1and at 1150 nm. Both bulk crystals and LPE films were used. At 1150 nm Sc substitution brings a net negative contribution to F.R. Also at 40K F.R. remains negative in the region 15000-21000 cm^-1. This is confirmed by\frac{\DeltaR}{R}measurements. MCD spectra indicate bands with a dominant character from a particular sublattice. Results are compared with Ga substitution. The band near 20800cm^-1is shown to be responsible for the negative F.R. observed, the contributions from bands at much higher energies compensate each other.