Wide bandwidth, low loss 1 by 4 wavelength division multiplexer on silicon for optical interconnects

We demonstrate an add/drop filter based on coupled vertical gratings on silicon. Tailoring of the channel bandwidth and wavelength is experimentally demonstrated. The concept is extended to implement a 1 by 4 wavelength division multiplexer with 6nm channel separation, 3nm bandwidth, a flat top response with < 0.8dB ripple within the 3dB passband, 1dB insertion loss and 16dB crosstalk suppression. The device is ultracompact, having a footprint < 2 X 10(-9)m(2). (C) 2011 Optical Society of America