Search results for "fiber"

A universal all-fiber omnipolarizer

2013

The all-optical control of light polarization is nowadays a fundamental issue which finds important applications in optical networks. In this field, the research has moved on the development of nonlinear methods of re-polarization of a partially coherent and initially depolarized light [1]. The main drawback of most of these devices is that they suffer from a large amount of output Relative-Intensity-Noise (RIN). However, a class of polarizers have been recently proposed which is based on the nonlinear interaction between two optical beams counter-propagating in a fiber [2]: in these devices the arbitrary state of polarization (SOP) of one of the two beams (signal) is attracted towards a sp…

A universal all-fiber Omnipolarizer

2014

We report the experimental observation of self-polarization of light in optical fibers through a counter-propagating four-wave mixing between an incident signal and its backward replica. An efficient self-polarization of a 40-Gbit/s signal is demonstrated.

Nonlinear dynamics induced by optical shocks formation

2006

This paper reports on recent studies suggesting that optical shocks can rule the dynamics of cw (or quasi-cw) optical field propagating in glass when common phenomena such as four-wave mixing in fibers or catastrophic self-focusing in bulk are considered. The post-shock oscillations evolve into colliding dark solitons that determine the output pattern in a non-recurrent fashion. This scenario based on the defocusing nonlinear Schrodinger equation and its reduction to a hydrodynamical model is substantially confirmed by our experimental data consisting of recorded output spectra and temporal patterns retrieved from SHG-FROG traces. Numerical results also indicate that, during self-focusing, …

Incoherent photonic techniques for RF-AWG

2010

The capabilities for RF-AWG in terms of waveform fidelity for three different incoherent photonic methods are revised and discussed: incoherent frequency-to-time mapping, incoherent MWP filtering with N discrete taps, and multi-wavelength pulse compression.

SOLITONS | Optical Fiber Solitons, Physical Origin and Properties

2005

Detection of the optical magnetic field by circular symmetry plasmons

2000

We report on the influence of coating a sharpened optical fiber tip with Au when observing nanofabricated dielectric structures with a Photon Scanning Tunneling Microscope (PSTM) in constant-height mode. For well-defined incident wavelengths and coating thicknesses, we found that such tips detect the distribution of the magnetic field associated with the optical wave in the near-field zone. A simple tip model indicates that this phenomenon is related to the excitation of circular symmetry plasmons in Au coated tips.

Actively Q-switched and modelocked all-fiber lasers

2010

Here we demonstrate active mode-locking (ML) and doubly-active Q-switching mode-locking (QML) of erbium-doped strictly all-fiber lasers. The active ML mechanism relies in the acoustooptic superlattice modulation (AOSLM) effect induced when longitudinal acoustic waves are launched along a fiber Bragg grating. In both regimes - ML as well as QML - we focus on the laser behavior when the AOSLM is driven by traveling acoustic waves, and next we compare these results with those obtained when the AOSLM is driven by standing acoustic waves. In the ML regime, optical pulses were obtained of 530 mW peak power, 700 ps temporal width, at a repetition rate of 4.1 MHz. On the other hand, in the QML regi…

Radiating and nonradiating behavior of hyperbolic-secant, raised-cosine, and Gaussian input light pulses in dispersion-managed fiber systems.

2005

We address the problem of optical light pulses, called dressed pulses, which do not match the stationary pulse profile of a dispersion-managed (DM) fiber system and we theoretically analyze the associated radiation. Comparing hyperbolic-secant, raised-cosine, and Gaussian pulse envelopes, we show that the general radiation figure is highly sensitive to the input pulse profile. As common general features for these pulse profiles, we find a rich variety of dynamical states that includes weak-, moderate-, and strong-radiation states, depending on the map strength of the DM fiber system. We demonstrate the existence of two intervals of map strengths where the emitted radiation is of considerabl…

All-fibered high-quality low duty-cycle picosecond high repetition rate pulse sources

2007

In this work, we demonstrate all-fibered 20-GHz and 40-GHz picosecond pulse sources with duty cycles as low as 1/14. The pulse train is achieved via the high-quality compression of an initial sinusoidal beating through four segments of optical fibers. We investigate the limits of the scalability to higher repetition rates.

Suppression of sideband frequency shifts in the modulational instability spectra of wave propagation in optical fiber systems

2007

International audience; In standard optical fibers with constant chromatic dispersion, modulational instability (MI) sidebands execute undesirable frequency shifts due to fiber losses. By means of a technique based on average-dispersion decreasing dispersion-managed fibers, we achieve both complete suppression of the sideband frequency shifts and fine control of the MI frequencies, without any compromise in the MI power gain.