Search results for "Mode locking"
showing 10 items of 10 documents
Structures optiques dissipatives en cavité laser à fibre
2011
This thesis presents a study of the nonlinear dissipative dynamics of localized of self organized structures in passively mode-locked fiber laser through nonlinear polarization evolution. We reveal the existence of a gradual transition from the quasi-cw to mode locked dynamics in the multi-pulsing regime. We emphasize on the intermediate state, where various new dynamics are observed. We study collective behaviors of dissipative solitons in the presence of a continuous background. One of the complex and attractive dynamics presented is the "soliton rain", which composed of three field components : continuous modes of background, drifting of solitons and condensed phase solitons. This dynami…
Universal soliton pattern formations in passively mode-locked fiber lasers
2011
International audience; We investigate multiple-soliton pattern formations in a figure-of-eight passively mode-locked fiber laser. Operation in the anomalous dispersion regime with a double-clad fiber amplifier allows generation of up to several hundreds of solitons per round trip. We report the observation of remarkable soliton distributions: soliton gas, soliton liquid, soliton polycrystal, and soliton crystal, thus indicating the universality of such complexes.
Generation of soliton molecules, power regulation, regeneration and sculpting of pulse profiles within a multifunction fiber laser
2018
The work of this thesis strives to provide a solution to the persistent problem of poverty of mode-locked fiber lasers, in terms of functionality and flexibility. The thesis proposes a fiber-laser cavity having the specificity of being multifunctional. The cavity is equipped with tunable components, which provide the flexibility to realize functions ranging from the generation of pulses with complex profiles (solitons, bi-solitons, tri-solitons, etc.) up to the carving of pulse profiles, passing through the regulation of peak powers, and the regeneration of severely degraded intensity profiles. The laser cavity that we propose has the specificity of being controlled by a key component, whic…
Q-switched mode locking noise-like pulse generation from a thulium-doped all-fiber laser based on nonlinear polarization rotation
2021
Abstract Q-switched mode locking (QML) noise-like pulse (NLP) emission from an all-fiber thulium-doped laser based on the nonlinear polarization rotation effect is reported. The QML emission is obtained in a cavity with net anomalous dispersion in a pump power interval in between the CW laser threshold and the threshold of the NLP regime. Highest-energy QML pulses were observed with a repetition rate of 812 kHz with a pump power of 520 mW at the optical wavelength of 1881.09 nm. A maximum overall energy of 460 nJ at an average output power of 6.4 mW was reached, which corresponds to a burst of mode-locked noise-like sub-pulses with 8.7 ns of pulse duration within a QML envelope of 11 µs. Th…
Highly-chirped similaritons generation from a mode-locked fiber laser
2007
In this communication, we report experimental and numerical results on dynamics and propagation of self-similar pulses in a passively mode-locked ytterbium doped DC fiber laser.
All polarization-maintaining assively mode-locked yb-doped fiber laser : pulse compression using an anomalous polarization-maintaining photonic cryst…
2019
We report the generation of short pulses at 1 μm using an all-polarization-maintaining (PM) fiber configuration. The pulses are provided by an all normal-dispersion Fabry-Perot Yb-doped cavity and are compressed with an anomalous polarization-maintaining photonic crystal fiber (PM PCF). Opposed to standard configurations; here the filtering action is solely performed by the finite bandwidth of the gain medium. The laser generates 8 ps width sech 2 profile pulses at 1046.8 nm with a −10 dB bandwidth of 5.9 nm. After compression using the PM PCF, pulses with an FWHM of 3 ps were obtained, limited by the actual value of the available anomalous dispersion. We also report the changes in the outp…
Silicon-microring into a fiber laser cavity for high-repetition-rate pulse train generation
2017
International audience; In 1997, Yoshida et al. inserted a Fabry-Perot filter in a modulation instability fiber laser cavity [1], the free spectral range (FSR) of the Fabry-Perot fixed the RF to 115 GHz; however the pulsed laser was poorly stable. Since then, lasers of increasing performance have been demonstrated using variants of this method. In 2012, Peccianti et al., demonstrated the first fiber laser harmonically mode-locked by integrated high-finesse microresonator [2]. The doped silica, on-chip microresonator provided both high spectral selectivity and nonlinearity, thus promoting the dynamics pulsed at 200 GHz. By using a silicon microring resonator (SMRR), this approach lead to the…
Stabilisation of modelocking in fibre ring laser through pulse bunching
2001
Bunching of equally spaced pulses is reported to be the most stable mode of operation in a passively modelocked fibre ring laser. The ring includes dispersion management, which results in the absence of strict pulse energy quantisation, giving pulse bunching a better immunity to environmental perturbation.
Optical Soliton Molecules in Fiber Lasers
2006
Recent experiments demonstrate that fiber laser cavities are able to support various multisoliton complexes, analogous to soliton molecules, which could have impact on optical information transmission or storage. These advances are guided by the concept of dissipative soliton.
A Coherent Master Equation for active mode locking in lasers
2015
We present the derivation of a new master equation for active mode locking in lasers that fully takes into account the coherent effects of the light matter interaction through a peculiar adiabatic elimination technique. The coherent effects included in our model could be relevant to describe properly mode-locked semiconductor lasers where the standard Haus’ Master Equation predictions show some discrepancy with respect to the experimental results and can be included in the modelling of other mode locking techniques too.