Non-reciprocal polarization rotation using dynamic refractive index modulation

Abstract

One of the most prominent classes of non-reciprocal devices relies upon the effect of non-reciprocal polarization conversion, such as those observed in Faraday isolators. This effect is usually achieved with the use of magneto-optical materials. Here, we introduce a waveguide type optical isolator based on non-reciprocal polarization conversion, without the use of magneto-optical materials. Our isolator is based on spatial-temporal dynamic refractive index modulation, which is more readily amenable for on-chip integration. We numerically demonstrate our design with both first-principle multi-frequency electromagnetic simulations and the vectorial coupled mode theory formalism.