Magnetooptics of the luminescent transitions in Tb3+:Gd3Ga5O12

Abstract The spectra of the luminescence and magnetic circular polarization of luminescence in terbium–gadolinium gallium garnet Tb 3+ :Gd 3 Ga 5 O 12 (Tb 3+ :GGG) were studied within the visible spectral range at temperatures T = 90 and 300 K in an external magnetic field of 0.45 T. The Zeeman effect in the luminescence “green” band associated with 4 f → 4 f transition 5 D 4 → 7 F 5 of Tb 3+ :GGG was also studied at T = 90 K in an external field of 0.55 T. Measurement of the Zeeman effect in Tb 3+ :GGG carried out for some doublet lines of the luminescence band 5 D 4 → 7 F 5 at T = 90 K shows that a magnetooptical effect of the intensity change of the emitted light is observed on these lines, in contrast to pure Zeeman splitting of the emission lines measured in the luminescence band 5 D 4 → 7 F 6 . For the systems we have studied, the maximal value of the magnetooptical effect of the intensity change of the luminescence line at low temperatures has been achieved in paramagnetic garnet Tb 0.2 Y 2.8 Al 5 O 12 at comparatively low magnetic fields.