OPTICAL-PERFORMANCE OF MINIATURE ALL-FIBER PHASE MODULATORS WITH ZNO COATING

Miniature all-fiber phase modulators with a radially symmetrical piezo electric ZnO jacket have been characterized using a Mach-Zehnder inter ferometer over a wide frequency range from 50 Hz to 50 MHz. The freque ncy response of the modulators consists of two flat broad-band regions and various resonances. The maximum phase shifts measured in the broa dband and resonance regions are 0.1 and 7.5 rad/V/meter of fiber, resp ectively. A linear dependence of the phase shift on the applied voltag e up to 60 V (peak-to-peak) is observed in the broad-band region.