Search results for "Nonlinear Optic"
showing 10 items of 530 documents
Modeling of the photorefractive nonlinear response in Sn_2P_2S_6 crystals
2007
We develop a theory of the photorefractive nonlinear response for Sn2P2S6 crystals. The theory incorporates two types of charge carrier (optically active and passive), provides explicit expressions for the characteristic buildup-relaxation rates and gain factors, explains naturally a big variety of accumulated experimental data, and facilitates characterization-optimization of this important nonlinear material.
Transverse nonlinear optics in heavy-metal-oxide glass
2008
6 pags. ; 9 figs.
Single-step arbitrary control of mechanical quantum states in ultrastrong optomechanics
2015
We describe how ultrastrong interactions in optomechanical systems can be used to force the system ground state to evolve into an arbitrary quantum state of mechanical motion in a completely controlled and deterministic manner. If the target quantum state is a superposition of $N$ Fock states, it can be obtained by applying in single-step $N$ classical optical signals of different frequencies for a common time interval. This protocol can be applied to various strongly interacting quantum systems as trapped ions beyond the Lamb-Dicke regime and cavity QED into the ultrastrong coupling regime.
Multiphase patterns in a degenerate nonlinear oscillator
2017
Degenerate four-wave mixing (DFWM) oscillators are phase-bistable devices. In such systems, two equivalent states, of equal intensities but opposite phases can be generated. When the cavity Fresnel number is large, different regions of the beam transverse section can have different phases, leading to phase patterns like phase fronts (or domain walls), i.e. ID structures separating regions with opposite phase that manifest as dark lines (as the phase jumps by π across the wall), phase domains, and phase solitons, among others.
Peculiarities of coherent optical oscillation in Sn_2P_2S_6 crystals
2010
We show analytically and numerically that the unusual photorefractive nonlinear response of Sn2P2S6 crystals leads to a variety of new features of coherent optical oscillation. In addition to the explanation of the known peculiarities, new features are predicted.
Bi-color spatial solitons in linearly uncoupled planar waveguides
2004
We report on the observation of spatial optical simultons in a novel geometry consisting of two partially overlapped, linearly uncoupled planar waveguides in lithium niobate obtained by reverse proton exchange. Two orthogonally polarized modes are coupled through an off-diagonal tensor element of the quadratic nonlinearity, giving rise to second harmonic generation and mutual trapping via cascading. This phenomenon demonstrates a balance between diffraction and self-focusing for two orthogonal modes of different waveguides, and occurs at room temperature in longitudinally uniform waveguides.
Experimental approach to transverse wave-number selection in cavity nonlinear optics
2004
Spontaneous transverse pattern formation is experimentally studied in a ${\text{BaTiO}}_{3}$ photorefractive oscillator under degenerate four-wave mixing conditions. A near self-imaging resonator of high Fresnel number and quasi-one-dimensional in the transverse plane is used. A fine control technique of the cavity detuning, $\ensuremath{\Omega}$, is described. It allows a precise study of the relation of $\ensuremath{\Omega}$ with the transverse wave number ${k}_{\ensuremath{\perp}}$ of the roll patterns selected by the system. The law ${k}_{\ensuremath{\perp}}^{2}=\ensuremath{-}\ensuremath{\Omega}∕a$ is verified, which evidences that wave-number selection is mainly dictated by the cavity …
Production and detection of atomic hexadecapole at Earth’s magnetic field
2007
We report a novel method that allows selective creation and detection of a macroscopic long lived hexadecapole polarization in the F = 2 ground state of 87Rb atoms at Earth's magnetic field (510 mG).
Even harmonics from laser driven homonuclear molecules
2007
The dynamics of a homonuclear diatomic molecule driven by a laser pulse is obtained beyond the fixed nuclei approximation. Laser parameters can be adjusted to confine the electron over one of the two nuclei for a relatively long time or not. A time-resolved analysis of the electromagnetic spectrum emitted by the molecule presents the usual odd harmonics far from confinement and even harmonics during the confinement periods. A physical interpretation of the results is given.
Self-similarity in ultrafast nonlinear optics
2007
International audience; Recent developments in nonlinear optics have led to the discovery of a new class of ultrashort pulse, the `optical similariton'. Optical similaritons arise when the interaction of nonlinearity, dispersion and gain in a high-power fibre amplifier causes the shape of an arbitrary input pulse to converge asymptotically to a pulse whose shape is self-similar. In comparison with optical solitons, which rely on a delicate balance of nonlinearity and anomalous dispersion and which can become unstable with increasing intensity, similaritons are more robust at high pulse powers. The simplicity and widespread availability of the components needed to build a self-similar amplif…