Search results for "continuum"
showing 10 items of 477 documents
Smooth and stable supercontinuum generation with standard photonic crystal fibers
2008
We identify some simple-to-fabricate photonic crystal fibers, with only two families of air-hole sizes, which provide a wide, smooth and highly-coherent supercontinuum.
Nonlinear spectral shaping and optical rogue events in fiber-based systems
2012
International audience; We provide an overview of our recent work on the shaping and stability of optical continua in the long pulse regime. Fibers with normal group-velocity dispersion at all-wavelengths are shown to allow for highly coherent continua that can be nonlinearly shaped using appropriate initial conditions. In contrast, supercontinua generated in the anomalous dispersion regime are shown to exhibit large fluctuations in the temporal and spectral domains that can be controlled using a carefully chosen seed. A particular example of this is the first experimental observation of the Peregrine soliton which constitutes a prototype of optical rogue-waves.
Spectral Slicing of a Supercontinuum Source for WDM/DS-OCDMA Application
2008
WDM and optical CDMA are leading contenders to easily upgrade access network performances in terms of multiple access technique. Both methods can be used at once, using a single multiwavelength optical source. We show, numerically and experimentally, that spectral slicing of a 10-GHz pulse train broadened to a supercontinuum yields pulses suitable for use in a direct sequence optical CDMA system. Simulations with optical CDMA encoders and decoders based on superstructured fiber Bragg gratings indicate good performance can be expected.
Novel spectra in the supercontinuum generation with applications in the biodiversity conservation
2014
This paper presents some spectra of the supercontinuum generation obtained with microstructured fibers and tapered fiber devices excited with quasi-continuous pumps. These spectra are part of a group (collection) of multiple configurations that were studied and evaluated by our working group, and that could be very useful in LIDAR as well as bio-imaging applications. This work is limited to present some spectra that could be useful in applications of biodiversity conservation. The prototypes for specific applications will be evaluated in future research.
Towards a Thermodynamic Description of Supercontinuum Generation
2009
Based on the kinetic wave theory, we describe continuous-wave supercontinuum generation as a thermalization process, i.e., an irreversible evolution of the optical field towards a state of maximum nonequilibrium entropy.
Visible Light Generation and Its Influence to Supercontinuum in As2S3 Microstructured Fiber
2011
We demonstrate visible light generation in As 2 S 3 microstructured fiber for the first time. It limits the spectral range of supercontinuum. The visible light generation can be avoided by designing the fiber for the single-mode operation.
Spectral and morphological analysis of the remnant of Supernova 1987A with ALMA and ATCA
2014
We present a comprehensive spectral and morphological analysis of the remnant of Supernova (SN) 1987A with the Australia Telescope Compact Array (ATCA) and the Atacama Large Millimeter/submillimeter Array (ALMA). The non-thermal and thermal components of the radio emission are investigated in images from 94 to 672 GHz ($\lambda$ 3.2 mm to 450 $\mu$m), with the assistance of a high-resolution 44 GHz synchrotron template from the ATCA, and a dust template from ALMA observations at 672 GHz. An analysis of the emission distribution over the equatorial ring in images from 44 to 345 GHz highlights a gradual decrease of the east-to-west asymmetry ratio with frequency. We attribute this to the shor…
Manufacturing of All-Fiber Q-Switch lasers for supercontinuum generation
2016
This work exposes the fabrication process of an All-Fiber Q-Switch laser and its use as a pump source for the generation of supercontinuum (SCG) with tapered microstructured fiber devices (tapers).
Nonlinear effects above 2 µm in chalcogenide suspended core microstructured optical fibers: Modeling and experiments
2011
We present our latest results on the linear and nonlinear modeling, and on the fabrication of chalcogenide suspended core microstructured optical fibers for mid-infrared generation. We focus on an AsSe glass composition. We have used a thulium-doped fiber laser to pump our fibers around 2 µm. In order to enhance further the nonlinearities and to manage the chromatic dispersion for supercontinuum application, we have tapered some of our microstructured optical fibers.
Quantum walks as simulators of neutrino oscillations in a vacuum and matter
2016
We analyze the simulation of Dirac neutrino oscillations using quantum walks, both in vacuum and in matter. We show that this simulation, in the continuum limit, reproduces a set of coupled Dirac equations that describe neutrino flavor oscillations, and we make use of this to establish a connection with neutrino phenomenology, thus allowing to fix the parameters of the simulation for a given neutrino experiment. We also analyze how matter effects for neutrino propagation can be simulated in the quantum walk. In this way, important features, such as the MSW effect, can be incorporated. Thus, the simulation of neutrino oscillations with the help of quantum walks might be useful to explore the…