Abstract: Described is an optical fiber system for delivering ultrashort pulses with minimal distortions due to nonlinearity. The system is based on delivering the optical pulses in a higher order mode (HOM) of a few-moded fiber. The fiber is designed so that the dispersion for the HOM is very large. This results in a dispersion length LD for the delivery fiber that is exceptionally small, preferably less than the non-linear length LNL. Under these conditions the system may be designed so the optical pulses experience minimum non-linear impairment, and short pulse/high peak power levels are reproduced at the output of the delivery fiber.

Abstract: An improved tapered fiber bundle (TFB), or assembly including a TFB, mitigates undesirable reflections from optical discontinuities at the input ends of the multimode fibers of the TFB by suppressing the coupling of signal light into modes that can produce undesired reflections. Means are provided for managing the mode field of injected signal light so that it remains substantially confined to the core of the central TFB fiber until it is past the region where it can interact with the multimode fibers of the TFB.

Abstract: Described is an optical fiber system for delivering ultrashort pulses with minimal distortions due to nonlinearity. The system is based on delivering the optical pulses in a higher order mode (HOM) of a few-moded fiber. The fiber is designed so that the dispersion for the HOM is very large. This results in a dispersion length LD for the delivery fiber that is exceptionally small, preferably less than the non-linear length LNL. Under these conditions the system may be designed so the optical pulses experience minimum non-linear impairment, and short pulse/high peak power levels are reproduced at the output of the delivery fiber.

Abstract: A filled-core optical fiber and method where the optical fiber is collapsed at opposing ends subsequent to the active optical material being introduced into the hollow core region. The collapsing-functions to “pinch off” the active material (which may be a liquid or solid) within the fiber structure and also collapse the cladding layer ring surrounding the core into a solid core region on either side of the active material. The filled-core fiber is then sealed and can be coupled to standard fiber using conventional splicing processes.

Abstract: An automatically adjustable arrangement for tuning the accumulated chromatic dispersion present in an optical communication system uses a dispersion variation-based measuring arrangement to determine both the magnitude and sign of the accumulated dispersion. A relatively small portion of a received optical signal including an unknown amount of chromatic dispersion is tapped off at an optical receiver and a small amount of additional dispersion is added to the tapped-off signal so that nonlinear detection can be used to determine both the magnitude and sign of the dispersion present in the transmission signal. This information is then fed back to a tunable dispersion compensator to provide the real-time, automatic correction to the dispersion present in the system.