Search results for "Active laser medium"
showing 8 items of 18 documents
The FURIOS laser ion source at IGISOL-4
2013
Abstract The FURIOS laser ion source at the Accelerator Laboratory of the University of Jyvaskyla has been moved to a new location as a part of the IGISOL-4 facility. The laser ion source project had a high priority which allowed the transport of laser light to be optimized during the design phase. The laser resonators have been upgraded with a dual etalon configuration leading to greatly reduced laser linewidth. The transport efficiency of the dual-chamber gas cell has been determined using an alpha recoil source, with efficiencies ranging from a few percent in the beam interaction chamber to nearly 20% in the ionization chamber. In addition, we present recent results from the re-commissio…
Temporal Soliton “Molecules” in Mode-Locked Lasers: Collisions, Pulsations, and Vibrations
2008
A few years after the discovery of the stable dissipative soliton pairs in passively mode-locked lasers, a large variety of multi-soliton complexes were studied in both experiments and numerical simulations, revealing interesting new behaviors. This chapter focuses on the following three subjects: collisions between dissipative solitons, pulsations of dissipative solitons, and vibrations of soliton pairs. Different outcomes of collisions between a soliton pair and a soliton singlet are discussed, showing possible experimental control in the formation or dissociation of ‘soliton molecules’. Long-period pulsations of single and multiple dissipative solitons are presented as limit cycles and o…
Multi-longitudinal mode emission in a bidirectional laser model
2011
Multi-longitudinal mode emission is a fundamental issue in laser physics. Interestingly enough, the mechanisms responsible for the transition from single- to multi-longitudinal mode emission have not been completely clarified yet. For example, it is well known that in unidirectional ring lasers the Rabi splitting of the lasing transition can lead to multimode emission even in a homogeneously broadened medium, the so called Risken-Nummedal—Graham-Haken instability (RNGHI) [1]. In spite of being known since the late sixties, only in the recent years a couple of experiments have demonstrated “dressed” versions of the RNGHI [2], i.e., up to day there are not clear demonstrations of this basic m…
Influence of light polarization on the dynamics of optically pumped lasers.
1990
The dynamic behavior of a coherently pumped ring laser with a homogeneously broadened four-level medium is analyzed theoretically, considering linearly polarized pump and generated laser beams. The laser is shown to be much more stable when these polarizations are parallel than when they are orthogonal. In the latter case the instability pump threshold can be as low as four times the first laser threshold, and the laser dynamics shows Lorenz-type features.
Comprehensive Theoretical and Experimental Study of Short- and Long-Term Stability in a Passively Mode-Locked Solitonic Fiber Laser
2015
We demonstrate the short- and long-term stable operation of an all-polarization-maintained Fabry–Perot cavity passively mode-locked fiber laser. The laser operates in an all-anomalous-dispersion solitonic regime. Laser stability is studied by a variety of measurements, which confirm the high stability of the laser in the temporal and spectral–both optical and electrical-domains. Pulse durations of 540 fs, period-relative time jitters of $\sim$ 0.015‰, and long-term uninterrumped operation with 0.4% variation (standard deviation) in the average output power are obtained. The highly stable operation of the laser oscillator was maintained after amplifying the laser output with a conventional E…
Passively mode-locked laser based on an ultra-large dispersion Yb-doped fiber
2013
Summary form only given. We report on the first realization of a passively mode-locked oscillator featuring an ultra-large dispersion Yb-doped Bragg fiber. The gain medium is a double-clad Bragg fiber featuring a 20 μm Yb-doped core surrounded by a 120 μm inner cladding [1]. The 2 m long gain fiber is cladding-pumped with a fiber-coupled laser diode emitting at 976 nm. Passive mode locking is achieved by the combined actions of nonlinear polarization evolution and a SESAM. Mode-locking is initiated by optimizing the saturation criteria on the saturable absorber mirror using an adequate focusing lens. The emission wavelength of the oscillator is controlled using a passive spectral filter int…
Glass-forming non-symmetric bis-styryl-DWK-type dyes for infra-red radiation amplification systems
2019
Abstract A series of D-π-A type organic dyes with bulky triphenylmethyl moiety containing 2,6-bis-(4-substituted)styryl-4H-pyran-4-ylidene donor (D) fragments and different electron acceptors (A) were synthesized and investigated, mostly for potential applications in organic solid-state lasers as infra-red (IR) radiation amplification medium. Dye glass transition temperature is above 99 °C with thermal stability in the region from 173 °C to 326 °C which was slightly influenced by the electron acceptor fragment attached to the 4H-pyrane ring in 4-position. Introducing substituents in 4-position within one of the styryl-fragments with stronger electron withdrawing properties decreased ASE exc…
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…