Analytical model of a Tellegen meta-atom

Tellegen response is a nonreciprocal effect that couples electric and magnetic responses of the medium and enables unique optical properties. Here, we develop a semi-analytical model of a Mie-resonant Tellegen meta-atom made of magneto-optical material and explicitly compute its magnetoelectric polarizability. We demonstrate that it could substantially exceed the geometric mean of electric and magnetic polarizabilities, giving rise to a strong and controllable effective Tellegen response in metamaterials.