Growth of {Tb₃}[Sc_2−<i>x</i>Lu_<i>x</i>](Al₃)O₁₂ Single Crystals for Visible-Infrared Optical Isolators

{Tb 3 }[Sc 2− x Lu x ](Al 3 )O 12 crystals have been grown and investigated for the first time for magneto-optical applications. Tb 3 Al 5 O 12 exhibits the best magneto-optical features; however, its incongruent melting nature has led to the industrial use of Tb 3 Ga 5 O 12 . Tb 3 Sc 2 Al 3 O 12 had been proposed as an alternative to Tb 3 Al 5 O 12, but unfortunately its growth also presents several drawbacks. The present investigation shows that by the isovalent substitution of Sc 3+ by Lu 3+ in the octahedral site of the garnet structure, it is possible to improve the growth characteristics while preserving the superior magneto-optical properties. We demonstrate that {Tb 3 }[Sc 2− x Lu x ](Al 3 )O 12 crystals show a higher visible transparency and a larger Faraday rotation than Tb 3 Ga 5 O 12 crystals. {Tb 3 }[Sc 2− x Lu x ](Al 3 )O 12 is therefore a very promising material in particular for new magneto-optical applications in the visible-near IR wavelength region.