Reversible switching of an optical gate based on Si rib waveguides with a Ge 2 Sb 2 Te 5 thin film

Reversible switching of an optical gate based on Si rib waveguides with a Ge 2 Sb 2 Te 5 thin film is reported. We demonstrated four cycles of switching by pulsed laser irradiation. The average extinction ratios of each switching event were 9.1, 10.7, 11.6 and 11.7 dB, respectively. The extinction ratio of this optical gate was more than 5.9 dB over the wide wavelength range from 1525 nm to 1600 nm.