Heterogeneous integration of EO polymers with micro-mechanical resonant structures

A method is introduced to mechanically bias an electro-optic (EO) polymer modulator by heterogeneous integration with mechanical resonant structures. Biasing is achieved by changing the path-length of one arm of a Mach-Zehnder (MZ) interferometer by mechanically bending the waveguide structure. Feasibility of integrating microelectromechanical systems with EO polymers is investigated, and the mechanical biasing concept is experimentally demonstrated by integrating EO polymer waveguides with a piezoelectric element (PZ). When a 3 kHz signal is applied to the PZ, a pilot tone is generated and its second harmonic (at 6 kHz) is minimized by applying DC voltage to the PZ, thus tuning the modulator to quadrature. This method avoids using external biasing components, eliminates electrical bias drift, and allows combination of the functions of biasing instrumentation on the modulator chip, thus reducing size, weight, and power consumption of the photonic link by 2 to 3 orders of magnitude.