Abstract

Traveling wave (TW) LiNbO₃ optical modulators with performance extending well into the millimeter-wave frequency spectrum have been recently reported [1,2]. In these devices, a near velocity match between microwave and optical signals was achieved by using thick electrodes [3] in a coplanar waveguide (CPW) configuration. For application of TW modulators in optoelectronic systems, a fundamental parameter of interest is the electrical to optical conversion loss. This loss limits the strength of the modulated optical signal and is primarily dependent on the RF Drive Voltage (V_π(f)). It is therefore of interest to measure V_π(f) directly. Below, we discuss a technique to carry out this measurement and compare results with theoretical calculations.

© 1993 Optical Society of America