MILLIMETER-WAVE TI-LINBO3 OPTICAL MODULATORS

The design, fabrication, and characteristics of ridged Ti:LiNbO3 optic al modulators that work in the millimeter-wave region are presented. A new concept of design under velocity matching is demonstrated for the proposed modulator. It has been shown by calculation that impedance m atching is achieved and conductor loss is greatly reduced under veloci ty matching with wider gaps and a thicker coplanar waveguide electrode in conjunction with a ridge structure. Two types of Mach-Zehnder opti cal intensity modulators for the wavelength of 1.5 mu m are developed. A fully packaged module for 40 Gb/s transmission with a half-wave vol tage of 3.5 V and a broadband modulator responsible up to 100 GHz with a half-wave voltage of 5.1 V.