Electro-optic Electric Field Sensor Utilizing Ti:LiNbO3 Symmetric Mach-Zehnder Interferometers

Abstract

The use of a Ti:LiNbO3 symmetric Mach-Zehnder interferometric intensity modulator with a push-pull lumped electrode and a plate-type probe antenna to measure an electric field strength is described. The modulator has a small device size of 46x7x1 mm and operates at a wavelength of 1.3 mu m. The output characteristic of the interferometer shows the modulation depth of 100% and 75%, and V-pi voltage of 6.6 V, and 6.6 V at the 200 Hz and 1 KHz, respectively. The minimum detectable electric field is similar to 1.84 V/m, similar to 3.28 V/m, and similar to 11.6 V/m, corresponding to a dynamic range of about similar to 22 dB, similar to 17 dB, and similar to 6 dB at frequencies of 500 KHz, 1 MHz and 5 MHz, respectively.