Large Bandwidth, highly Efficient Mode-Coupling Using Long-Period Gratings in Dispersion Tailored Fibers

We report the first demonstration of strong (>99%) coupling in long-period fiber-gratings over bandwidths as large as 30 nm. Though gratings are resonant devices, phase matching can be achieved over a broad range of wavelengths by suitably tailoring the dispersion properties of the fiber. Polarization dependence studies of these novel gratings show that the polarization dependent coupling varies by only 0.02% over the entire spectrum.