Abstract-Terahertz response of gadolinium gallium garnet (GGG) and gadolinium scandium gallium garnet (SGGG)

Mohsen Sabbaghi, George W. Hanson, Michael Weinert, Fan Shi, Cheng Cen

https://arxiv.org/abs/2001.05085

We report the magneto-optical response of Gadolinium Gallium Garnet (GGG) and Gadolinium Scandium Gallium Garnet (SGGG) at frequencies ranging from 300GHz to 1THz, and determine the material response tensor. Within this frequency window, the materials exhibit nondispersive and low-loss optical responses. At low temperatures, significant THz Faraday rotations are found in the (S)GGG samples. Such strong gyroelectric response is likely associated with the high-spin paramagnetic state of the Gd3+ ions. A model of the material response tensor is determined, together with the Verdet and magneto-optic constants.