Title :
Si Photonic Wire Waveguide Devices
Author :
Yamada, Hirohito ; Chu, Tao ; Ishida, Satomi ; Arakawa, Yasuhiko
Author_Institution :
Fundamental Res. Labs., NEC Corp., Ibaraki
Abstract :
Si photonic wire waveguides are attractive for constructing various optical devices that are extremely small because the waveguides can be bent with extremely small curvatures of less than a few micrometers of bending radius. We have fabricated optical directional couplers with the waveguides and demonstrated their fundamental characteristics. Their coupling length was extremely short, several micrometers, because of strong optical coupling between the waveguide cores. We have also demonstrated wavelength-demultiplexing functions for these devices with a long coupled waveguide. Optical outputs from a device with a 100-mum-long coupled waveguide changed reciprocally with a 20-nm wavelength spacing between the parallel and cross ports. We also demonstrated the operation of ultrasmall optical add-drop multiplexers (OADMs) with Bragg grating reflectors made up of the waveguides. The dropping wavelength bandwidth of the OADMs was less than 0.7 nm, and these dropping wavelengths could be precisely designed by adjusting the grating period. Using the Si photonic wire waveguide, we have also demonstrated thermo-optic switches. Metal thin-film heaters were evaporated onto the branch of a Mach-Zehnder interferometer that incorporated the waveguide to achieve switching operations by thermo-optic effects. In these switching operations, we observed more than 30 dB of extinction ratio, less than 90 mW of switching power, and less than 100 mus of switching speed
Keywords :
Bragg gratings; demultiplexing; integrated optics; light interferometry; mirrors; multiplexing equipment; optical communication equipment; optical directional couplers; optical switches; optical waveguides; silicon; thermo-optical devices; thermo-optical effects; 100 mum; Bragg grating reflectors; Si; Si waveguide devices; bending radius; coupled waveguide; optical add-drop multiplexers; optical coupling; optical devices; optical directional couplers; optical waveguides; photonic wire devices; switching operations; thermooptic effects; waveguide cores; wavelength-demultiplexing functions; Bragg gratings; Directional couplers; Optical add-drop multiplexers; Optical coupling; Optical devices; Optical interferometry; Optical waveguides; Ultraviolet sources; Waveguide transitions; Wire; Integrated optics; Si-wire thermo-optic effects; lightwave circuit; optical add-drop multiplexer (OADM); optical directional coupler; optical interconnection; optical switch; optical waveguide; silicon-on-insulator (SOI);
Journal_Title :
Selected Topics in Quantum Electronics, IEEE Journal of
DOI :
10.1109/JSTQE.2006.880611