Optical interactions

B. DiBartolo, Optical Interactions in Solids,]ohxi Wiley Sons, Inc., New York, 1968, for a quantum mechanical description. 

Availability of an intermediate focus (after the quaternary mirror) for the calibration of adaptive optics interaction matrices. 

McConnell and Weaver, using the nmr line width method, have obtained a value for the observed rate coefficient, for the reaction in 12 M hydrochloric acid media, of 5 x 10 l.mole . sec. The width of the Cu NMR line from copper(I) ( 1 M) was observed in the presence of copper(II) (10 to 10 M). In this media the exchanging species are probably CuCl4 and CuCls . Optical interaction effects have been observed in mixtures of Cu(I) and Cu(II) in chloride media. ... 

Nonlinear Optical Interactions in Organic Crystal Cored Fibers... 

Non-linear optical interactions occur in materials with high optical intensities and have been used to produce coherent light over a wide range of frequencies from the far infra-red to the ultra-violet. The three wave mixing process is of particular interest as it can be used for optical parametric amplification and optical second harmonic generation (SHG) and occurs in non-centrosymmetric materials. 

We believe that our model can be extended even further to accurately describe other nonlinear optical interactions such as sum and difference frequency mixing, as well as higher-order harmonics generation. 

I. Biaggio, P. Kerkoc, L.S. Wu, P. Gunter, and B. Zysset, Refractive-indexes of orthorhomhic KNbOs Phase-matching configurations for nonlinear-optical interactions, Journal of the Optical Society of America B 9(4), 507-517 (1992). 

In this expression, designates the distance of closest approach which is of the order of the root a of the interaction potential. The duration of optical interactions is then simply given by... 

Classification of Lidar System. Lidar systems can be classified on die basis of particular optical interactions which they utilize Classes of lidar include ... 

Interest in the field of nonlinear optics has grown tremendously in recent years. This is due, at least partially, to the technological potential of certain nonlinear optical effects for photonic based technologies. In addition, the responses generated through nonlinear optical interactions in molecules and materials are intimately related to molecular electronic structure as well as atomic and molecular arrangement in condensed states of matter. 

In the above equation a is the linear polarizability. The terms 3 and Y, called first and second hyperpolarizabilities, describe the2 nonlinear optical interactions and are microscopic analogues of x and x... 

There is an inherent similarity between the spectrum and an electrochemical current-voltage curve that is important from the point of view of chemical selectivity. In both cases, the x-axis (voltage or wavelength) is directly related to the energy. In electrochemistry, this energy corresponds to the transfer of electrons between the analyte and the electrode. It is related to the standard electrochemical potential. In optical interactions, molar absorptivity is probabilistically related to the excitation energy of the molecule. 

Consider first the simpler case of acousto-optic interaction in an isotropic medium (i.e. a standard acousto-optic modulator). If the wavevector of the incident light is ko, that of the scattered light k+ or k and that of the phonon K, we have for conservation of momentum... 

Nanometer scale domain configurations in fe bulk crystals pave the way for a new class of photonic devices. As an example, preliminary calculations show that a uv laser (A = 300 nm) based on second harmonic generation in LiTaC>3 crystal requires a periodic nanodomain superlattice with domain widths of around 700 nm. In addition, the current domain gratings in ferroelectric crystals are suitable only for quasi-phase-matched nonlinear interactions in the forward direction, where the pump and generated beams propagate in the same direction. Sub-micron ferroelectric domain gratings are the basis for a new family of devices based on backward nonlinear quasi-phase-matched optical interactions in which the generated beam travels in a reverse or another non-collinear direction to the incident beam. Non-collinear... 

BaO was produced by allowing barium vapour in an argon carrier to interact with traces of oxygen. Microwave power was introduced by means of a simple horn situated close to the optical interaction zone. By tuning the dye laser frequency to coincide exclusively with a succession of rovibronic transitions, it was possible to observe and measure four rotational transitions in the X 1 + ground state, involving both v = 0 and v = 1, and thirteen rotational transitions in the A 1 X excited electronic state. From these measurements accurate values of the rotational constants were obtained, particularly for the excited state. 

Nano-structured Metals Enhanced Optical Interactions with Materials. 163... 

Di Bartolo B (1968) Optical interactions in solids. Wiley, New York... 

Near-field scanning optical microscopy (NSOM) has been developed as a combination of scanning probe microscope and optical microscope in which the spatial resolution is determined by scanning probe microscope resolution while the signals detected are coming from several optical interactions. As a result, NSOM has achieved a higher spatial resolution than that of the classical optical microscopy that uses a conventional lens, which is strictly limited by the diffraction... 

As a probe of lattice vibrations, Raman spectroscopy is very sensitive to intrinsic crystal properties and extrinsic stimuli, especially in semiconductors. It may be employed to study crystal structure and quality, crystal orientation, optical interactions, chemical composition, phases, dopant concentration, surface and interface chemistry, and local temperatme or strain. As an optical technique, important sample information may be obtained rapidly and nondestructively with minimal sample preparation. Submicron lateral resolution is possible with the use of confo-cal lenses. These features have made it a vital tool for research labs studying semiconductor-based technologies. They also are increasingly important for the study of semiconductor NWs fabricated by both top-down and bottom-up approaches since many of the common characterization methods used with bulk crystals or thin films cannot be applied to NWs in a direct manner. 

The profoundly different optical interactions in subwavelength dielectric wires noted in the introduction lead to considerable differences in Raman scattering intensities from bulk crystal samples as well as strong polarization dependencies. Such phenomena arise from the effects of geometric confinement on light scattering due to the boundary mismatch of the dielectric function at optical frequencies. 

A particularly important variant of the optical force, interparticle forces, turns out to be crucial for SERS. This effect is similar to the attractive van der Waals force between small particles, which is due to interactions between spontaneously fluctuating dipoles, but the optical interaction is due to coupling between the actual particle dipoles induced by the trapping laser. Due to the interparticle optical forces, metal nanoparticles aggregate in an optical tweezers and produce hotspots, i.e., particle junctions with intense local fields for SERS. Raman probes can be excited either by the trapping laser or, preferably, by a separate low power beam that does not disturb the trapping. 

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