Analysis and optimum design of a polymer Y-fed coupler electro-optic switch using double-section reversed electrodes.

A packaged polymer electro-optic switch using double-section reversed electrodes based on the Y-fed coupler structure is investigated in terms of the conformal transforming method, image method, coupled mode theory and electro-optic modulation theory. The structure and principle are described, and unique formulations are proposed for simulating the device, including the amplitude transfer matrix, propagation powers and output powers. Design and optimization are performed, and characteristics are analyzed. Under the central operation wavelength of 1550 nm, the coupling region length is 4391.5 µm, the driving voltages of the upper and lower branches are as low as +0.633 and -0.633 V, respectively; the insertion loss and crosstalk are less than 2.04 and -30 dB, respectively, within the relative large ranges of fabrication error and wavelength shift. The proposed analysis and formulations are proved to be sufficiently accurate by comparison with the beam propagation method (BPM). The designed switch with the above waveguide and electrode structure shows lower switching voltage compared to our previous reported switches. [ABSTRACT FROM AUTHOR]