A Photonic Microwave Filter Based on an Asymmetric Silicon Mach-Zehnder Modulator

A new approach for implementing an integrable photonic microwave filter based on exploiting the asymmetry of a CMOS-compatible silicon Mach-Zehnder modulator is demonstrated. The strong dependence of the modulator response with wavelength is exploited for achieving positive and negative taps and, therefore, a fully reconfigurable filter, without the complexity of previous approaches. Two filter responses with two and three taps are experimentally demonstrated, showing the proof-of-principle for frequencies up to 10 GHz and thus going one step further toward a full integration of the complete filter device in the CMOS-compatible silicon photonics platform.