Abstract
<jats:p>The Faraday effect in a material describes the interaction between a linearly polarized laser wave and a static magnetic induction oriented parallel to the direction of propagation of the light wave. The polarization of the light undergoes a rotation that is proportional to the applied magnetic induction, the distance travelled within the material and the Verdet constant of the material. This magneto- optical phenomenon is used in particular in optical isolators, especially for frequency- stabilized lasers and high-power sources, to prevent any back-reflected light into the cavity that could destabilize or damage the device. Accordingly, magneto-optical materials are key components in optical isolators using the Faraday rotation and they are of paramount importance for high-power solid-state laser applications. In particular, terbium-based single crystals exhibit several advantages such as a wide optical transparency range, low optical absorption, high thermal stability, strong Faraday effect, magnetic field sensing capability, and a high signal-to- noise ratio. Besides, they operate in the ultraviolet (UV), visible (VIS) and near infrared (NIR) optical range. This chapter deals with the crystal growth and the magneto-optical properties of particularly efficient materials, Tb3 Ga5 O12 (TGG), KTb3 F10 (KTF) and Tb2 O3 in these spectral regions, as well as their use in experimental setups for designing adaptable optical isolators.</jats:p>