Scattering of light by spheres made from a time-modulated and dispersive material

We derive the dispersion relation of eigenmodes propagating in a time-varying and dispersive medium. We use these eigenmodes to analytically study the scattering of light by a sphere made from a time-varying and dispersive medium. These results are compared to full-wave optical simulations and excellent agreement is observed. With that, we provide tools and outline a path towards further explorations of light scattering by time-varying finite particles.