Self-holding magneto-optical switch integrated on silicon photonic platforms

We demonstrated what we believe to be a novel self-holding waveguide switch integrated on silicon photonic platforms utilizing the magneto-optical (MO) effect with electrical switching operation. In this study, we designed thin-film magnet arrays and electrodes positioned beside the waveguide. The switching states were changed by flipping the magnetization of thin-film magnets with an applied current of 700 mA, and the switching states were successfully maintained with zero current. The fabricated MO switch has an extinction ratio (ER) of 16.5 dB and an insertion loss (IL) of 7.3 dB at a wavelength of 1546.2 nm, with a phase shift of π/2. This study shows the potential of self-holding silicon photonic switches, enabling large-scale photonic integrated circuits with extremely low energy consumption.