Dual on-fiber thin-film heaters for fiber gratings with independently adjustable chirp and wavelength

Dual, independently addressable thin-film resistive heaters fabricated in a multilayer geometry on the surface of an optical fiber provide a new, flex ible means for thermally tuning the properties of intracore gratings. In pa rticular, control of the current that is applied to each of these heaters p ermits the chirp and the central wavelength of the grating to be adjusted i ndependently. The designs and simple fabrication procedures for these types of device, the important physics of heat flow in them, and a tunable add-d rop filter that demonstrates essential aspects of their operation are descr ibed. (C) 1999 Optical Society of America.