Magnetic optical activity in Bi-doped Mg–Al–Si glass

We report the results of the experiments on the magnetic optical activity in Bi-doped Mg–Al–Si oxide glass in the temperature range of 1.48–200 K and high magnetic fields—up to 6.5 T. Temperature dependences of the magnetic circular polarization of luminescence and magnetic circular dichroism indicate the spin multiplicity of the ground and excited states. The investigated system has at least three different defect centers. Experimental data are explained in the assumption of an even-electron system with axial and rhombic zero-field splitting components.