Polymeric electro-optic Mach–Zehnder switches

Polymeric 2×2 electro-optic switches based on the balanced bridge, or Mach–Zehnder, design are presented. Two poled nonlinear optical side-chain polymers based on the dye Disperse Red 1, one with a glass transition temperature Tg of 131 °C and the other with a Tg of 228 °C, were used as the active layers in these devices. The switch designs incorporated traveling-wave electrodes in the phase shift sections and, for the lower Tg polymer device, electrically adjustable 3 dB couplers. At the 1.32 μm operating wavelength, extinction ratios of at least 28 dB were achieved in all four states of the lower Tg switch with a propagation loss of 1.6 dB/cm and a small signal 3 dB modulation bandwidth of over 2 GHz.