Measurement of resonant and nonresonant induced refractive index changes in Yb-doped fiber grating amplifier.

Fiber amplifier utilizing an Yb-doped large-mode-area fiber with confined doping and tailored refractive index profile

Power scaling of Yb-doped large-mode-area fibers drives the scaling of the mode area in order to suppress nonlinearities. Two Yb-doped large-mode-area fibers were manufactured using the Direct Nanoparticle Deposition process: one with a step refractive index profile and active ion confinement, and another with a tailored refractive index and active ion confinement. The index tailoring and dopin...

Pump induced refractive index changes in commercial single-mode Yb-doped optical fibers

We have explored the refractive index changes (RIC) in single-mode aluminum silicate ytterbium-doped optical fibers induced by optical pulses at 980 nm and report dynamical fundamentals of the process. The RIC dynamics is shown to follow the population dynamics of the excited and unexcited ions with a factor proportional to their polarizability difference (PD). The PD dispersion profile indicat...

Resonantly Induced Refractive Index Changes in Yb-doped Fibers: the Origin, Properties and Application for all-fiber Coherent Beam Combining

Picosecond pump-probe interferometric measurement of optical nonlinearity in semiconductor-doped fibers.

Refractive and absorptive optical nonlinearity can be distinguished using a pump-probe interferometric technique with picosecond time resolution. The method is applied to both resonant and nonresonant nonlinearities in optical fibers and reveals marked differences between the relaxation behavior of the refractive and absorptive nonlinearity in certain cases. A monomode fiber doped with CdS(x)Se...

Optimization of Bistability in Nonlinear Chalcogenide Fiber Bragg Grating for All Optical Switch and Memory Applications

We solve the coupled mode equations governing the chalcogenide nonlinear fiber Bragg gratings (FBGs) numerically, and obtain the bistability characteristics. The characteristics of the chalcogenide nonlinear FBGs such as: switching threshold intensity, bistability interval and on-off switching ratio are studied. The effects of FBG length and its third order nonlinear refractive index on FBG cha...