1.55 μm reflection-type optical waveguide switch based on SiGe/Si plasma dispersion effect

Based on total internal reflection and plasma dispersion effect, a SiGe/Si asymmetric optical waveguide switch with transverse injection structure has been proposed and fabricated. The switch performance is measured at the wavelength of 1.55 μm. A modulation depth of 90% at an injection current of 110 mA is obtained, and the switching time is about 0.2 μs. The device reaches a maximum optical switching at the injection current of 120 mA. The extinction ratio is larger than 34 dB and the crosstalk and insertion loss are less than −18.5 and 2.86 dB, respectively.