Reflection-type optical waveguide switch with bow-tie electrode

Abstract

Based on the total internal reflection and the plasma dispersion effect of SiGe alloy, an intersectional rib optical waveguide switch with bow-tie electrode has been proposed and fabricated for the wavelengths of 1.3- and 1.55-μm operation. The thickness of SiGe layer is 2.6 μm and the width is 9 μm. The branch angle of the switch is 2° and the bow-tie angle is 1.5°. The crosstalks are - 19.6 dB for 1.3 μm and -21.8 dB for 1.55 μm. At both wavelengths, the extinction ratio is larger than 38.5 dB and the insertion loss is less than 1.70 dB. The switching time is about 180 ns.