Improving characteristic of Faraday effect based on the Tm3+ doped terbium gallium garnet single crystal

• Highly transparent Tm:TGG crystal was firstly grown by the Czochralski method.
• The Verdet constant of Tm:TGG crystal is enhanced at VIS-NIR region.
• The crystal obtains high thermal conductivity and laser induced damage threshold.
• The crystal is suitable for new and improved Faraday rotators.

Highly transparent Tm3+ doped terbium gallium garnet single crystal was grown by the Czochralski(Cz) method for magneto-optical applications. The single-crystal X-ray diffraction confirms that the compound crystallize in the cubic systems with the structure a = b = c = 1.2338 nm. The temperature dependence of the magnetic susceptibility indicates that the Tm:TGG crystal exhibits paramagnetic behavior over the experimental temperature-range 10–300 K. Transmittance spectra and the Faraday rotation have been investigated, which demonstrates that the as-grown crystal shows a high visible transparency and yields a lager Faraday rotation comparable to that of TGG crystal. The increasing of the Verdet constant at measured wavelength and high thermal property show the superior characteristics of Tm3+ doped TGG compared to the pure TGG, indicating that it has significant development for magneto-active materials used in Faraday devices at visible and near-infrared regions (VIS-NIR).