561 research outputs found
Analytical method for designing dispersion-managed fiber systems
This paper was published in Optics Letters and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.opticsinfobase.org/abstract.cfm?URI=ol-26-20-1544. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.Peer reviewedPublisher PD
Quadratic cavity soliton optical frequency combs
We theoretically investigate the formation of frequency combs in a dispersive second-harmonic generation cavity system, and predict the existence of quadratic cavity solitons in the absence of a temporal walk-off
Optimal frequency conversion in the nonlinear stage of modulation instability
We investigate multi-wave mixing associated with the strongly pump depleted
regime of induced modulation instability (MI) in optical fibers. For a complete
transfer of pump power into the sideband modes, we theoretically and
experimentally demonstrate that it is necessary to use a much lower seeding
modulation frequency than the peak MI gain value. Our analysis shows that a
record 95 % of the input pump power is frequency converted into the comb of
sidebands, in good quantitative agreement with analytical predictions based on
the simplest exact breather solution of the nonlinear Schr\"odinger equation
Polarization domain wall complexes in fiber lasers
International audienceWe present a simple theoretical model that explains polarization switching in fiber ring lasers operating with a normal path-averaged dispersion and a typical intermediate level of birefringence. Such polarization dynamics, based on a type of polarization-domain-wall (PDW) structures, agree qualitatively well with our experimental observations. We also stress the complex and chaotic nature of the observed polarization-switching states. This is corroborated by detailed numerical simulations that predict the buildup of consecutive and transient PDW structures at the subnanosecond scale, which are not fully resolved experimentally
Simplified high-order Volterra series transfer function for optical transmission links
We develop a simplified high-order multi-span Volterra series transfer function (SHMS-
VSTF), basing our derivation on the well-known third-order Volterra series transfer function
(VSTF). We notice that when applying an approach based on a recursive method and considering
the phased-array factor, the order of the expression for the transfer function grows as 3 raised to
the number of considered spans. By imposing a frequency-flat approximation to the higher-order
terms that are usually neglected in the commonly used VSTF approach, we are able to reduce
the overall expression order to the typical third-order plus a complex correction factor. We carry
on performance comparisons between the purposed SH-MS-VSTF, the well-known split-step
Fourier method (SSFM), and the third-order VSTF. The SH-MS-VSTF exhibits a uniform
improvement of about two orders of magnitude in the normalized mean squared deviation with
respect to the other methods. This can be translated in a reduction of the overall number of steps
required to fully analyze the transmission link up to 99.75% with respect to the SSFM, and
98.75% with respect to the third-order VSTF, respectively, for the same numerical accuracy
A universal optical all-fiber omnipolarizer
Wherever the polarization properties of a light beam are of concern, polarizers and polarizing beamsplitters (PBS) are indispensable devices in linear-, nonlinear-and quantum-optical schemes. By the very nature of their operation principle, transformation of incoming unpolarized or partially polarized beams through these devices introduces large intensity variations in the fully polarized outcoming beam(s). Such intensity fluctuations are often detrimental, particularly when light is post-processed by nonlinear crystals or other polarization-sensitive optic elements. Here we demonstrate the unexpected capability of light to self-organize its own state-of-polarization, upon propagation in optical fibers, into universal and environmentally robust states, namely right and left circular polarizations. We experimentally validate a novel polarizing device-the Omnipolarizer, which is understood as a nonlinear dual-mode polarizing optical element capable of operating in two modes-as a digital PBS and as an ideal polarizer. Switching between the two modes of operation requires changing beam's intensity
Locking of domain walls and quadratic frequency combs in doubly resonant optical parametric oscillators
The formation of frequency combs (FCs) in high-Q microresonators with Kerr type of nonlinearity has attracted a lot of attention in the past decade [1]. Recently it has been shown that FCs can be also generated in dissipative dispersive cavities with quadratic nonlinearities [2,3], opening a new possibility of generating combs in previously unattainable spectral regions. Previous work has shown that modulational instability (MI) induces pattern and FC formation in degenerate optical parametric oscillators (OPOs) [4]. However, the existence of dissipative solitons or localized structures (LSs) is still unclear
Random mode coupling assists Kerr beam self-cleaning in a graded-index multimode optical fiber
In this paper, we numerically investigate the process of beam self-cleaning in a graded-index multimode optical fiber, by using the coupled-mode model. We introduce various models of random linear coupling between spatial modes, including coupling between all modes, or only between degenerate ones, and investigate the effects of random mode coupling on the beam self-cleaning process. The results of numerical investigations are in complete agreement with our experimental data
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