Cascaded Mach-Zehnder wavelength filters in silicon photonics for low loss and flat pass-band WDM (de-) multiplexing

We present 1-to-8 wavelength (de-) multiplexer devices based on a binary tree of cascaded Mach-Zehnder-like lattice filters, and manufactured using a 90 nm CMOS-integrated silicon photonics technology. We demonstrate that these devices combine a flat pass-band over more than 50% of the channel spacing with low insertion loss of less than 1.6 dB, and have a small device size of approximately 500 x 400 mu m. This makes this type of filters well suited for application as WDM (de-) multiplexer in silicon photonics transceivers for optical data communication in large scale computer systems. (C) 2013 Optical Society of America