Search results for "four-wave mixing"
showing 10 items of 97 documents
Wavelength shift of four-wave mixing bands in photonic crystal fibers pumped in the normal dispersion regime
2011
The generation of correlated photon pairs plays a central role in several quantum mechanics applications, such as quantum information, and cryptography [1]. Correlated photon pairs can be generated inside an optical fiber through the parametric process of degenerated four-wave mixing (FWM) [2]. In this paper we report the results of two different experiments where wavelength shift of FWM bands in normal dispersive PCFs is investigated.
Integrated Generation of High-dimensional Entangled Photon States and Their Coherent Control
2017
Exploiting a frequency-domain approach, we demonstrate the generation of high-dimensional entangled quantum states with a Hilbert-space dimensionality larger than 100 from an on-chip nonlinear microcavity, and introduce a coherent control platform using standard telecommunications components.
Continuous Lyman-alpha generation by four-wave mixing in mercury for laser cooling of antihydrogenThis paper was presented at the International Confe…
2011
Cooling antihydrogen atoms is important for future experiments both to test the fundamental CPT symmetry by high resolution laser spectroscopy and also to measure the gravitational acceleration of antimatter. Laser cooling of antihydrogen can be done on the strong 1S–2P transition at the wavelength of Lyman-alpha (121.6 nm). A continuous wave laser at the Lyman-alpha wavelength based on solid-state fundamental lasers is described. By using a two-photon and a near one-photon resonance a scan across the whole phase matching curve of the four-wave mixing process is possible. Furthermore the influence of the beam profile of one fundamental beam on the four-wave mixing process is studied.
Spontaneous symmetry breaking as a resource for noncritically squeezed light
2010
[EN] In the last years we have proposed the use of the mechanism of spontaneous symmetry breaking with the purpose of generating perfect quadrature squeezing. Here we review previous work dealing with spatial (translational and rotational) symmetries, both on optical parametric oscillators and four-wave mixing cavities, as well as present new results. We then extend the phenomenon to the polarization state of the signal field, hence introducing spontaneous polarization symmetry breaking. Finally we propose a Jaynes-Cummings model in which the phenomenon can be investigated at the singlephoton-pair level in a non-dissipative case, with the purpose of understanding it from a most fundamental …
Absolute instability in backward wave four-wave mixing: spatial effects
2010
The spatial distribution of new beams generated above the threshold of absolute instability of two counterpropagating incoherent light waves is studied and compared with the results of calculation.
Four-wave mixing instabilities in telecom fibers
2012
Instabilities in fiber four-wave mixing are investigated, revealing the formation of colliding dispersive shock waves in the normal GVD regime and collective modulation instabilities in the anomalous GVD regime.
160-GHz picosecond pulse train generation through multiwave mixing compression of a dual frequency beat signal
2002
We report the experimental generation and characterization of a 160-GHz picosecond puise train using multiple four-wave mixing temporal compression of an initial dual frequency beat signal in the anomalous-dispersion regime of a non-zero dispersion shifted fiber.
Impact of fourth-order dispersion in the modulational instability spectra of wave propagation in glass fibers with saturable nonlinearity
2010
We analyze the modulational instability (MI) of light waves in glass fibers with a local saturable nonlinear refractive index. We identify and discuss the salient features of the effect of the fourth order of the fiber dispersion, in the MI spectra. Particularly, we find that in fibers with negative sign of the second-order dispersion and positive sign of the fourth-order dispersion (FOD), the two existing types of MI processes, called processes of type I, which generate a single pair of sidebands, and processes of type II, which lead to two pairs of sidebands, become highly sensitive to the magnitude of the FOD, both quantitatively and qualitatively. We demonstrate the existence of a criti…
<title>Phase conjugation properties of a-As-S-Se films</title>
2006
Light wavefront inversion (phase conjugation) in a-As-S-Se films has been studied experimentally. Phase conjugation (PC) of plane and spherical waves is carried out in a-As40S15Se45 films using degenerate four-wave-mixing (DFWM) geometry at 633 nm. In the plane wave case simultaneous PC efficiency and DE measurements have been made versus exposure time, light intensity and holographic grating period. The maximal PC efficiency was 2.3% and the minimal PC specific recording energy was 2 J/(cm2%) whereas the maximal DE was 0.9% and the minimal specific hologram recording energy was 10 J/(cm2%). The optimal grating period was 2 μm. When compared to a-Se films a-As-S-Se films exhibit lower PC ef…
Four-wave mixing control in the filamentation of ultrafast Bessel beams via longitudinal intensity-shaping
2017
International audience; Bessel beams exploit conical energy flow to yield near-uniform intensity along a line focus which has been shown to be extremely attractive for laser processing in dielectrics. At high power, however, the nonlinear Kerr effect is known to induce significant oscillations of the on-axis intensity which is deleterious for machining applications. Here, we show through theory and numerical modelling how this problem can be understood and overcome by appropriate spatial phase shaping of the input profile. Our results also solve the longstanding problem related to the nonlinear Bessel beam dynamics seen at an air-dielectric interface.