Integrated Hybrid VO2-Silicon Optical Memory

Vanadium dioxide (VO2) is an interesting material for hybrid photonic integrated devices due to its insulator-metal phase transition. Utilizing the hysteresis of the phase transition in voltage-biased VO2, we demonstrate a compact hybrid VO2-silicon optical memory element integrated into a silicon waveguide. An optical pulse writes the VO2 memory, leading to an optical attenuation that can be read out by the optical transmission in a silicon waveguide. Our on-chip memory cell can be optically written with energy as low as 23.5 pJ per pulse and with a 10-90% rise time of similar to 100 ns. This approach is promising for optical data storage in silicon photonic integrated circuits.