Title :
Nonlinear absorption and Raman scattering in silicon-on-insulator optical waveguides
Author :
Tak-Keung Liang ; Hon-Ki Tsang
Author_Institution :
Dept. of Electron. Eng., Chinese Univ. of Hong Kong, China
Abstract :
We study the nonlinearities in silicon-on-insulator (SOI) optical waveguides, which include two-photon absorption (TPA), free-carrier absorption, and spontaneous and stimulated Raman scattering (SRS). We show experimentally that free carriers generated by TPA in the SOI waveguides produce large optical loss at room temperature. The experimental results confirmed the presence of relative optical signal amplification from SRS, but it was found that net gain was hardly achieved because the stimulated Raman gain was less than the induced loss from TPA-generated free carriers at room temperature with continuous-wave pumping source in a SOI rib waveguide. We also experimentally investigated the temperature dependence of Raman scattering in the SOI waveguide and observed the Raman gain to be greater than TPA-generated free-carrier absorption loss at 77 K.
Keywords :
optical losses; optical waveguides; silicon-on-insulator; stimulated Raman scattering; two-photon processes; SOI waveguide; TPA; free-carrier absorption; nonlinear absorption; optical loss; optical signal amplification; room temperature; silicon-on-insulator optical waveguides; spontaneous Raman scattering; stimulated Raman scattering; two-photon absorption; Absorption; Nonlinear optics; Optical losses; Optical pumping; Optical scattering; Optical waveguides; Raman scattering; Silicon on insulator technology; Stimulated emission; Temperature; Amplification; Raman scattering; optical waveguides; silicon waveguides; silicon-on-insulator (SOI); two-photon absorption (TPA);
Journal_Title :
Selected Topics in Quantum Electronics, IEEE Journal of
DOI :
10.1109/JSTQE.2004.835290
