Compensating loss with gain in slow-light propagation along slab waveguide with anisotropic metamaterial cladding

We explore slow-light propagation in a dielectric slab waveguide with anisotropic metamaterial cladding, which could be realized through multilayer structure with alternating metal and dielectric films. We show that although the loss in the realistic metamaterial will destroy the zero-energy velocity condition, the loss effect can be fully compensated by incorporating gain in the core material, which recovers the stopping and storing of light propagation in the waveguide. We demonstrate full-wave electromagnetic simulations on the realistic waveguide that validate our theoretical analysis.