POLYMER IN-LINE FIBER MODULATORS FOR BROAD-BAND RADIOFREQUENCY OPTICAL LINKS

We present a polymer in-line fiber modulator with a rugged and low-los s interface to single-mode fibers that can be engineered to have a bia s point that yields Linear modulation over a large dynamic range. Two classes of large-bandwidth modulators, each of which benefits from dif ferent properties provided by polymers, are demonstrated. A lumped cap acitor modulator, which uses a decal deposition technique, and a trave ling-wave modulator, which takes advantage of polymer conformal coatin g and reactive ion etching to accurately trim the thickness of the pol ymer waveguide, are presented. Because the in-line fiber modulator con figuration requires moderate loss Do achieve a large dynamic range, an operational wavelength closer to the absorption peak of an electro-op tic polymer can be used to exploit the resonant enhancement of electro -optic coefficients. (C) 1998 Optical Society of America.