Infiltrated bunch of solitons in Bi-doped frequency-shifted feedback fibre laser operated at 1450 nm

Abstract

Mode-locked fibre laser as a dissipative system is characterized by rich forms of soliton interaction, which take place via internal energy exchange through noisy background in the presence of dispersion and nonlinearity. The result of soliton interaction was either stationary-localized or chaotically-oscillated soliton complexes, which have been shown before as stand-alone in the cavity. Here we report on a new form of solitons complex observed in Bi-doped mode-locked fibre laser operated at 1450 nm. The solitons are arranged in two different group types contemporizing in the cavity: one pulse group propagates as bound solitons with fixed phase relation and interpulse position eventuated in 30 dB spectrum modulation depth; while the other pulses form a bunch with continuously and chaotically moving solitons. The article describes both experimental and theoretical considerations of this effect.

All-optical fiber soliton processing using dispersion oscillating fiber

“…The generation of the rogue-like wave in DOF can be controlled by adjusting the modulation period and the temporal separation between the peak of the initial pulses. Mode-locked lasers can demonstrate generation packets of closely spaced pulses [46][47][48][49]. Soliton fusion can be used for converting pulse packets into new pulses with increased peak power.…”

Supermode noise suppression of the harmonically mode-locked fiber laser through continuous wave injection: experiment and numerical simulations

“…A shift of the soliton carrier frequency occurs due to phase-locking between the soliton and the CW component that in some sense works as the dispersive wave generated by the soliton. It is known that the soliton spectrum frequency shift provokes an accelerated evolution of the perturbed HML system to an equilibrium state improving the regularity of pulse arrangement in the cavity [6,11,18]. Although this understanding has no contradiction with the reported experimental observations, neither theory nor numerical simulations have been presented until now to prove or disprove the hypothesis and model the underlying mechanisms.…”

“…In the harmonic mode-locking (HML) regime the multiple pulses are evenly spaced inside the cavity and the laser emits regular pulses with much higher PRR equal to an integer multiple of the fundamental PRR [6][7][8][9][10]. The HML could be implemented in the fiber laser cavity using a special intracavity periodic filter [8,[11][12][13] or through active mode-locking procedure [14,15]. However, the most attractive way is the use of the passive harmonic mode-locking mechanism exploiting the pulse repulsion in the ring laser cavity [6][7][8][12][13][14][15][16][17][18].…”

Soliton Raman shift wavelength tuning through the pump pulse polarization control

“…One of the approaches to fiber lasers developing in these wavelength regions is the application of Bismuth, Thulium or Holmium doped fibers with luminescence window in this spectral range [18][19][20][21]. Nevertheless, despite the unique optical properties of these fibers and significant achievements in their applications, the widespread use of such schemes is limited by the lower availability and higher cost of special fiber-optic components (isolators, lenses, multiplexers, semiconductor mirrors, etc.)…”