Single-mode electric-field-sensitive fiber jacketed with vinylidene fluoride–trifluoroethylene copolymer

An integrated phase modulator is made by coating single-mode fibers with a radially poled vinylidene fluoride-trifluoroethylene copolymer. The performance of the fiber as an optical phase modulator was demonstrated over a wide frequency range of 20-50 MHz. A phase sensitivity of 2.1 x 10(-5) rad/(V/m) per meter of fiber is measured in the low-frequency region and 3.5 x 10(-6) rad/(V/m) per meter of fiber is measured in the high-frequency region. At frequencies higher than 1 MH(z), the optical response is dominated by radial resonances of the fiber-jacket composite.