Tunable dispersion compensators utilizing higher order mode fibers

We demonstrate a novel tunable dispersion compensator that utilizes higher order mode fibers and switchable fiber gratings. The device is broad band and wavelength continuous, yielding a bit rate, bit format, and signal bandwidth as well as channel-spacing transparent adjustable dispersion compensator. The novel device design is free from tradeoffs between tuning range and bandwidth. The tuning range is 435 ps/nm, with a bandwidth of 30 nm. Its all-fiber configuration yields the lowest loss (average /spl sim/3.7 dB) tunable dispersion compensator reported to date. 40-Gb/s transmission tests reveal penalty-free operation.