107 research outputs found
Factorization of Numbers with the temporal Talbot effect: Optical implementation by a sequence of shaped ultrashort pulses
We report on the successful operation of an analogue computer designed to
factor numbers. Our device relies solely on the interference of classical light
and brings together the field of ultrashort laser pulses with number theory.
Indeed, the frequency component of the electric field corresponding to a
sequence of appropriately shaped femtosecond pulses is determined by a Gauss
sum which allows us to find the factors of a number
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
Direct fluorescence characterisation of a picosecond seeded optical parametric amplifier
The temporal intensity contrast of high-power lasers based on optical parametric amplification (OPA) can be limited by parametric fluorescence from the non-linear gain stages. Here we present a spectroscopic method for direct measurement of unwanted parametric fluorescence widely applicable from unseeded to fully seeded and saturated OPA operation. Our technique employs simultaneous spectroscopy of fluorescence photons slightly outside the seed bandwidth and strongly attenuated light at the seed central wavelength. To demonstrate its applicability we have characterised the performance of a two-stage picosecond OPA pre-amplifier with 2.8×105 gain, delivering pulses at 1054 nm. We show that fluorescence from a strongly seeded OPA is reduced by ~500× from the undepleted to full pump depletion regimes. We also determine the vacuum fluctuation driven noise term seeding this OPA fluorescence to be 0.7±0.4 photons ps−1 nm−1 bandwidth. The resulting shot-to-shot statistics highlights a 1.5% probability of a five-fold and 0.3% probability of a ten-fold increase of fluorescence above the average value. Finally, we show that OPA fluorescence can be limited to a few-ps pedestal with 3×10−9 temporal intensity contrast 1.3 ps ahead of an intense laser pulse, a level highly attractive for large scale chirped-pulse OPA laser systems
THz pulse generation and single shot detection in a single ZnTe Crystal IRMMW- THz 2022
Single-cycle THz signal of few picoseconds duration, have been simultaneous generated via optical rectification and detected by electro-optic effect in the same ZnTe crystal. An unbalanced seemingly single shot detection scheme was performed to characterize the signal. The added simplicity of this scheme aided the independent analysis of the horizontal and vertical polarization arm of the chirped probe beam to explain the associated nonlinearities in the detected THz signal
THz Spectroscopic Characterization of Oil Shales, IRMMW-THz 2022
Grey to dark-grey samples reported to be oil shales have been analyzed under the THz reflection and transmission spectroscopy. In order to examine the organic and mineral stratification of the oil shales, samples at varying height above the ground level were excavated from stream banks and hilly terrains. The constituent of these aquatic and terrestrial-based oil shales were further correlated to investigate any correspondence or dissimilarities in their composition by examining the refractive index, absorption and optical path length maps of the samples
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
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
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