Reflective duplexer based on silicon micromechanics for fiber-optic communication

In this paper, we report on a passive duplexer based on reflective modulation for single-mode fibers. The component integrates a silicon micromechanical modulator and a photoreceiver in a hybrid assembly. Fabricated by the silicon micromachining technology reflective modulators allow a considerable cost reduction of single mode fiber-optic links as compared to systems operating with active light sources at both link terminals. The micromechanical modulator is characterized by a low insertion loss of less than 3 dB and polarization insensitivity. The ON-OFF ratio is typically 9 dB over a wavelength range from 1260 to 1360 nm. The operation frequency is limited by the mechanical movement of the modulator membrane to 1.3-2 MHz. We report on the characterization of fully packaged duplexer components.