Correlation between multiple modulation instability side lobes in dispersion oscillating fiber

We investigate numerically and experimentally the spectral correlation between multiple modulation instability (MI) side lobes in a dispersion oscillating fiber. By leveraging the dispersive Fourier transformation, we acquire instantaneous spectra and investigate the energy correlation between individual MI sidebands through scattergrams. We found that conjugate MI side lobes are strongly correlated while other combinations experience a very low degree of correlation, revealing that parametric processes related to each side lobe pair act quasi-independently.published_or_final_versio

Computing prime factors with a Josephson phase qubit quantum processor

A quantum processor (QuP) can be used to exploit quantum mechanics to find the prime factors of composite numbers[1]. Compiled versions of Shor's algorithm have been demonstrated on ensemble quantum systems[2] and photonic systems[3-5], however this has yet to be shown using solid state quantum bits (qubits). Two advantages of superconducting qubit architectures are the use of conventional microfabrication techniques, which allow straightforward scaling to large numbers of qubits, and a toolkit of circuit elements that can be used to engineer a variety of qubit types and interactions[6, 7]. Using a number of recent qubit control and hardware advances [7-13], here we demonstrate a nine-quantum-element solid-state QuP and show three experiments to highlight its capabilities. We begin by characterizing the device with spectroscopy. Next, we produces coherent interactions between five qubits and verify bi- and tripartite entanglement via quantum state tomography (QST) [8, 12, 14, 15]. In the final experiment, we run a three-qubit compiled version of Shor's algorithm to factor the number 15, and successfully find the prime factors 48% of the time. Improvements in the superconducting qubit coherence times and more complex circuits should provide the resources necessary to factor larger composite numbers and run more intricate quantum algorithms.Comment: 5 pages, 3 figure

Chirped pulse amplification in a fiber optical parametric amplifier

Proc. SPIE 7728, Nonlinear Optics and Applications IV, Brussels, Belgium, April 12, 2010Fiber optical parametric amplifiers (FOPAs) have attracted considerable attention during the last decade because of their broad bandwidth, high gain and wavelength-flexibility. In comparison to cumbersome bulky systems, they bring the advantages of all-fiber systems, i.e. reliability, long-term stability and compactness. FOPAs rely on the third-order susceptibility and are characterized by a quasi-instantaneous nonlinear response that involves pump, signal and idler waves. Chirped pulse amplification (CPA) allows to get a high energy amplification and its realization in FOPAs would increase the overall performances of these amplifiers. Such an experimental demonstration has never been reported in the past. In this work, we show for the first time the experimental feasibility of fiber-based optical parametric chirped pulse amplification (FOPCPA) with an all-fibered setup. The stretching/compression stages are realized with a single linearly chirped fiber Bragg grating (LCFBG) used in both directions while the amplification is performed in a CW-pumped FOPA that uses 500 meters of highly nonlinear fiber (HNLF). Fourier transform limited optical pulses at 1550 nm are stretched from 6 ps to 70 ps and then amplified by 22 dB without any spectral or temporal distortions. Experiments are confirmed by simulations carried out by numerical integration of the nonlinear Schrödinger equation with parameters matching those of the experimental setup. For simplicity, this first experimental demonstration is realized in the telecommunication window. By using photonic crystal fibers, one can move the working wavelength around 1 μm

O papel social e economica da mulher imigrante na região de Venda Nova do Imigrante (ES) - 1891 A 1927

Dissertação apresentada no Pragrma de Pós- Graduação de Históri

Observation of energetic protons trapped in laboratory magnetic-tower jets

Preliminary results of the self-emission of charged particles from magnetically driven plasma jets has been investigated. The jets were launched and driven by a toroidal magnetic field generated by introducing a ∼1.4 MA, 250 ns electrical current pulse from the MAGPIE generator into a radial wire array. This configuration has shown to reproduce some aspects of the astrophysical magnetic-tower jet launching model, in which a jet is collimated by a toroidal magnetic field inside a magnetic cavity. The emission of ions and protons from the plasma was recorded onto Columbia Resin 39 plates using timeintegrated pinhole cameras. In addition a fly-eye camera, an array of 25–496 cylindrical apertures allowed estimating the location of the ion emitting source. The results show the ion emission comes from both the jet and its surrounding magnetic cavity, with the emission extending to a height of at least ∼9 cm from the initial position of the wires. The emission of ions is consistent with the dynamics of the jet obtained from time-resolved imaging diagnostics, i.e. optical laser probing and self-emission of the plasma in the extreme ultra-violet. These preliminary results suggest the ions are trapped inside the cavity due to the strong toroidal magnetic field which drives the jet. In addition these studies provide first estimates of the energy and fluence of protons for future laser-driven proton probing diagnostics aimed at measuring the magnetic field in these experiments

Temporal Contrast of Tunable Ultrashort Pulses Generated in the Near Infrared

International audienceA laser source delivering ultrashort pulses (50-100 fs) tunable from 820 nm to 1200 nm has been recently developed. It is based on the filtering of a continuum in the Fourier plane of a zero dispersion line without any phase compensator. In the manuscript, we investigate how the temporal contrast from the pump is transferred to the tunable ultra-short pulses. We demonstrate that in addition to the wide tunability, this method allows to enhance the temporal contrast by at least two orders of magnitude. This enhancement at relativement long time is efficient for the complete tunable range but it depends strongly on the spectral bandwidth of each pulse. We also show that the filter profile has a weak impact on the temporal contrast at long time (few ps). Hence, the spectral filtering can be achieved directly in a stretcher (or a compressor) with hard cuts. This new approach can be of great interest for laser-matter interaction experiments in the strong field when it is combined with optical parametric amplifiers

Modulation Instability in a dispersion oscillating fiber pumped by a broad band pulse

International audienceWe numerically investigate the modulation instability generated in a dispersion oscillating fiber pumped by a chirped pulse with a broad bandwidth. We highlight that the side bands are wide, not symmetric in frequency about the pump and several instantaneous side bands can spectrally overlap with each other in one side while they are well located in the other side. We also show that the spectral distribution can be intuitively explained with an analogy in which the fiber is pumped by a tuneable continuous wave

Experimental demonstration of a synthetic aperture compression scheme for multi-Petawatt high-energy lasers

International audienceWe present the experimental demonstration of a subaperture compression scheme achieved in the PETAL (PETawatt Aquitaine Laser) facility. We evidence that by dividing the beam into small subapertures fitting the available grating size, the sub-beam can be individually compressed below 1 ps, synchronized below 50 fs and then coherently added thanks to a segmented mirror. " Split-aperture laser pulse compressor design tolerant to alignment and line-density differences

Generation of tunable ultrashort pulses in the near infrared

A laser source delivering ultrashort pulses (50-100 fs) tunable from 820 nm to 1200 nm has been developed. It is based on the filtering of a continuum in the Fourier plane of a zero dispersion line without a phase compensator. We have also numerically investigated the impact of the residual spectral phase in order to guarantee ultrashort pulses