Search results for " photonic"
showing 10 items of 720 documents
Advanced Optical Processing of Microwave Signals
2005
The authors present a review on the recent approaches proposed to implement transversal RF filters. Different tunable transversal filters consisting of wavelength tunable optical taps and those employing the tunability of dispersive devices are presented showing their high-performance characteristics. A comprehensive review of the fundamentals and a discussion on the main limitation of these structures are also included.
Parallel Recording of Single Quantum Dot Optical Emission Using Multicore Fibers
2016
Single Indium Arsenide Quantum Dot emission spectra have been recorded using a four-core, crosstalk-free, multicore fiber placed at the collection arm of a confocal microscope. We developed two different measurement set-ups depending on the relative configuration of the excitation and collection spots. In the single-matched mode, the emission from the excited area is collected by a single core in the multicore fiber, whereas the three remaining cores capture the emission from neighboring, non-excited areas. This procedure allows for the recording of the Quantum Dot emission from carrier diffusion between sample positions separated by more than 6 μm. In the multiple-matched mode, the ex…
Shallow water rogue wavetrains in nonlinear optical fibers
2013
International audience; In addition to deep-water rogue waves which develop from the modulation instability of an optical CW, wave propagation in optical fibers may also produce shallow water rogue waves. These extreme wave events are generated in the modulationally stable normal dispersion regime. A suitable phase or frequency modulation of a CW laser leads to chirp-free and flat-top pulses or flaticons which exhibit a stable self-similar evolution. Upon collision, flaticons at different carrier frequencies, which may also occur in wavelength division multiplexed transmission systems, merge into a single, high-intensity, temporally and spatially localized rogue pulse.
All-optical measurements of background, amplitude, and timing jitters for high speed pulse trains or PRBS sequences using autocorrelation function
2008
International audience; We present a simple method for all-optical measurements of background, amplitude, and timing jitters of ultra high speed pulse trains or PRBS sequences using the jitter dependence of the intercorrelation-peak shape. This method is numerically and experimentally demonstrated on a 42.66 Gbit/s PRBS sequence and then applied to measure the jitter growths occurring during the propagation of a 160-GHz pulse train in a classical SMF/DCF dispersion map.
Multiple four-wave mixing in optical fibers: 1.5–3.4-THz femtosecond pulse sources and real-time monitoring of a 20-GHz picosecond source
2010
International audience; In this work, we report recent progress on the design of all-fibered ultra-high repetition-rate pulse sources for telecommunication applications around 1550 nm. The sources are based on the non-linear compression of an initial beat-signal through a multiple four-wave mixing process taking place into an optical fiber. We experimentally demonstrate real-time monitoring of a 20 GHz pulse source having an integrated phase noise 0.01 radian by phase locking the initial beat note against a reference RF oscillator. Based on this technique, we also experimentally demonstrate a well-separated high-quality 110 fs pulse source having a repetition rate of 2 THz. Finally, we show…
Design of a continuously tunable delay line using vectorial modulational instability and chromatic dispersion in optical fibers
2009
International audience; We design an all-optical tunable delay line based on both dispersive and wavelength conversion stages involving modulational instability of a two-frequency pump field propagating in a highly birefringent fiber. More precisely, we numerically show that, by varying the frequency separation between the two orthogonally polarized pump waves, we achieve a controllable and continuous delay of hundreds of picoseconds for signal pulse durations from picoseconds to nanoseconds, without pulse distortion and with only small peak power fluctuations. The proposed method does not require any tunable bandpass filter and can be applied to delay digital data streams at tens of Gbit/s…
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.
Two-wave interferences space-time duality: Young slits, Fresnel biprism and Billet bilens
2017
International audience; Taking advantage of the analogy that can be drawn between the spatial and temporal propagations, we explore two-wave temporal interference in textbook cases such as Young's double slits, Fresnel's biprism and Billet's bilens. We illustrate our approach by numerical simulations for short pulses propagating in dispersive optical fibers with parameters typical of those found in modern optical telecommunications.
Theory of modal attraction in bimodal birefringent optical fibers
2013
Nonlinear mode coupling among two beams of different wavelength that copropagate in a bimodal highly birefringent optical fiber may lead to the effect of modal attraction. Under such circumstances, the modal distribution of light at a pump wavelength is replicated at the signal wavelength, nearly irrespective of the input mode excitation conditions of the signal.
Polarization modulation instability in a Manakov fiber system
2015
International audience; The Manakov model is the simplest multicomponent model of nonlinear wave theory: It describes elementary stable soliton propagation and multisoliton solutions, and it applies to nonlinear optics, hydrodynamics, and Bose-Einstein condensates. It is also of fundamental interest as an asymptotic model in the context of the widely used wavelength-division-multiplexed optical fiber transmission systems. However, although its physical relevance was confirmed by the experimental observation of Manakov (vector) solitons in a planar waveguide in 1996, there have in fact been no quantitative experiments confirming its validity for nonlinear dynamics other than soliton formatio…