Self-induced nonreciprocal transmission with optical nonlinear metamaterials

Breaking the Lorentz reciprocity law and consequently generating nonreciprocal transmission consists a fundamental functionality in several important optical devices such as isolators, circulators, switches, and optical diodes. Self-induced nonreciprocity based on optical nonlinear effects is a more appealing technique compared to other relevant nonreciprocal schemes due to the absence of any kind of external bias based on magnets, currents, or space and time modulation. Therefore, the nonlinearity-based nonreciprocal photonic devices are expected to have an ultrafast response and low cost and be compact in size and easy to implement. Hence, they are ideal for on-chip integration and free-space optics applications.