Nanowaveguide Designs in 220-nm SOI for Ultra-broadband FWM at Telecom Wavelengths

We present optimal designs for nanowaveguides on standard 220-nm SOI platform yielding ultra-broadband phase-matching over bandwidths >500-nm spanning the entire telecommunication spectrum (O-, E-, S-, C-, L-, U- bands, ~1250-1750 nm) for degenerate-pump four-wave mixing (FWM). A complete study of FWM bandwidth as a function of waveguide dimensional parameters like width, etching depth and sidewall slant-angle is presented. Extensive numerical mode simulations show that the proposed device designs exhibit promising tolerances towards fabrication inaccuracies. These designs can be used for WDM (wavelength division multiplexing) systems in classical optical communication and/or broadband photon-pair sources for multi-channel quantum communication.