Fabrication and characterization of TGG crystals containing paramagnetic rare-earth ions

Superexchange Interaction Influence on the Faraday Effect in Terbium Fluorophosphate Glasses by Co-doping with Praseodymium, Dysprosium, and Holmium

“…The only modified parameters are the substitution value and the nature of the substituent. The superexchange interaction induced by co-doping is assumed to be at the origin of this behavior, as previously reported in TAG and TGG co-doped crystalline materials in the literature. ,,,,,, …”

“…The substitution with other trivalent RE ions should then tend to decrease the Verdet constant. In the literature, assumptions to explain this phenomenon consider the influence of the crystal field, the spin–orbit coupling, and more especially the superexchange interaction ,,,,,, corresponding to the exchange of an electron via the overlapping of the orbitals between two cations separated by an anion. , …”

Tb3Al2.5 Ga2.5O12 transparent ceramic for magneto‐optical application

“…Characterization results showed that the Tb 3 Al 2.5 Ga 2.5 O 12 transmittance was close to 80% in the 500‐1600‐nm region, which was the highest transparency among these three samples. The Verdet constant of the Tb 3 Al 2.5 Ga 2.5 O 12 ceramic at 632.8 nm measured at room temperature was −150.6 rad/Tm, which is 12% larger than that of the pure TGG single crystal (−134.1 rad/Tm) and 13% smaller than that of the pure TAG single crystal (‐174.3 rad/Tm) . Based on a comparison of the Tb 3 Al 2.5 Ga 2.5 O 12 ceramic optical properties, crystal structures, microstructures, and magneto‐optical properties with those of the TGG and TAG ceramics, it is apparent that the high‐doping‐concentration (Tb 3 Al 2.5 Ga 2.5 O 12 ) TGAG ceramic developed in this work is a promising candidate for magneto‐optical applications in the visible and near‐IR regions.…”

High Verdet Constant Materials for Magneto-Optical Faraday Rotation: A Review

“…The general formula for naturally occurring garnets is X 3 Y 2 (SiO 4 ) 3 ; however, numerous synthetic garnets (such as those mentioned previously) with different metal oxide matrices have been developed which replace the Si atoms with Al, Ga, or Fe. These crystals are often prepared using traditional growth methods such as the Czochralski process or the Float Zone method to produce high quality materials. , The typical range of Verdet constants for these materials at room temperature in the visible and IR spectrum (400–1600 nm) are on the order of 10 4 °/T·m, ,− although Verdet constants as high as 10 5 °/T·m were achieved under cryogenic conditions (see Figure crystals). , RE fluoride crystals are a class of single crystal MO materials that possess Verdet constants similar to garnet crystals but are often optimized for high power laser systems. RE-fluoride crystals such as potassium terbium fluoride (KTF) are promising materials for multikilowatt average-power Faraday isolators, reporting peak Verdet constants of ∼6.50 × 10 3 °/T·m at 633 nm (Figure ).…”

“…Verdet constants of lanthanide glasses − (red square), diamagnetic ion glasses ,,− , (red circle), chalcogenide glasses − (red triangle), nanoparticle-glass composites − (red pentagon), garnet crystals ,− ,,− (green square), RE fluoride crystals − (green circle), other MO crystals − (green triangle), garnet-based ceramics − ,− (blue square), and sesquioxide-based ceramics − (blue circle) plotted to show general trends of peak Verdet constants of inorganic materials. The labels TSAG and TGG are terbium scandium aluminum garnet and terbium gallium garnet, respectively.…”