Large bandwidth, highly efficient mode coupling using long-period gratings in dispersion tailored fibers

We report the demonstration of strong (>20 dB) coupling in long-period fiber-gratings over bandwidths as large as 43 nm. These novel spectra are obtained by suitably tailoring the dispersion properties of a fiber. The polarization dependent coupling for the mode-converters varies by less than 0.004% over the entire spectrum.