Spectral division amplification of a 40 nm bandwidth in a multicore Yb doped fiber and femtosecond pulse synthesis with in-fiber delay line.

A compact multicore ytterbium doped fiber amplifier has been implemented according to the spectral division scheme. It was shown that it allows amplification of pulses with about 40 nm wide spectrum. Compensation of the different spectral bands delay through bending and twist of the multicore ribbon fiber followed by appropriate setting of their phase permitted the synthesis of pulses close to 100 fs duration.

Dual-wavelength synchronous ultrashort pulses from a mode-locked Yb-doped multicore fiber laser with spatially dispersed gain.

A laser based on a ribbon multicore ytterbium doped fiber where different cores amplified different spectral bands, has been mode-locked with a single saturable absorber mirror. Tunable dual wavelength synchronized picosecond pulses were obtained. Compensation of differential cavity roundtrip times was achieved in the fiber.

Spatially dispersive amplification in a 12-core fiber and femtosecond pulse synthesis by coherent spectral combining.

A compact scheme is demonstrated for amplification and synthesis of ultrashort pulses by fiber amplifiers. Femtosecond pulses are split in 12 different spectral bands which are amplified separately in the 12 cores of a multicore ytterbium doped fiber. Combining the amplifier outputs together with the intensity and phase management of the spectral bands lead to short pulse synthesis with adjustable pulse shape. The scheme gave an x 92 enhancement in amplified power before the onset of nonlinear effects by comparison with standard stretcher free amplification in a single core fiber.

Spatially dispersive scheme for transmission and synthesis of femtosecond pulses through a multicore fiber.

A new scheme is presented for fiber transmission of ultrashort laser pulses. A dispersive device divides the input pulses into spatially separated spectral components which are individually launched in the different channels of a multicore fiber before being recombined at the output by a second dispersive device. The parallel transmission of narrow spectral bands avoids self-phase modulation and could be appropriate to deliver high peak power pulses. Phase management of the spectral bands by an active element offers recovery of the seed pulse duration at the fiber output as well as pulse shaping capabilities. Both are reported in a proof of concept experiment using 190 fs input pulses and a 5 cores polarization maintaining fiber. Extension of the concept to femtosecond pulses amplification is suggested.