When two of three pairs of the Gaussian laser beams of a traditional MOT are misaligned in the "racetrack" configuration the effective coordinate-dependent vortex force do arise. Then an atom is accelerated by this vortex force until its velocity not balanced by the damping force. This situation may produce a stable ring of revolving atoms of a certain radius. Due to the different frequency and laser beams intensity dependences of the vortex, damping and trapping forces it is possible to equalize the radii of two orbiting groups of atoms in two-species or dual-isotope magneto-optical trap and so to arrange a continuing collider of cooled atoms with the prescribed relative velocity. A collider setup for atoms of two different types rotating with different angular velocities along the same ring-like trajectory into MOT of the conventional six-beam geometry is proposed and designed on example of two rubidium isotopes Rb85 and Rb87.
KEYWORDS: Dielectrics, Reflectivity, Metals, Reflectometry, Grazing incidence, Refractive index, Beam splitters, Sensors, Signal detection, Signal to noise ratio
A new technique to obtain the real and imaginery parts of the dielectric function of an absorbing medium in terms of the ration R'p/R's of the derivatives of p and s polarized light reflectances at the grazing and the normal incidence is developed. IT is shown that this ratio can be expressed through the logarithmic derivatives (1/R)R' in the vicinity of the grazing angle. The using of both the normal - incidence and near- grazing angles measurements allows to overcome the instability (extreme sensitivity to experimental error) of all inversion of the polarized reflectances methods for absorbing media. The possibility of this method is verified by the Jacobian formalism. It is important that errors in the measured parameters are not magnified when calculating the optical constants from the experimental data. We propose the practical implementation of this method with variation of the angle of incidence in an optical fashion. IT permits to perform all the measurements appreciably aside from the grazing angle and greatly enhance the accuracy of these measurements.
Using the generalized method of integral equations we developed the technique for the macroscopic description of any multicomponent medium with allowance of a discreteness of a medium for the first time in molecular optics. Proceeding from the microscopic parameters of the medium we derive the dielectric response and the nonlinear susceptibilities of a two-component crystal.
We extended the method of integral equations to weakly rarefied media when the distance between the radiators is not negligibly small in comparison with the light wavelength. This enables us to calculate the local fields and the dielectric permittivity of some regular and chaotic media.
Due to its simplicity polarization reflectometry technique have some advantages over the ellipsometric methods. We demonstrate this claim in the threefold manner suggesting three novel polarization reflectometry methods for the determination of an optical anisotropy. The first method is based on the measurement of s- and p- polarized light reflectances under near normal or grazing angles (or both) and of the Brewster angle. It may be applied to any uniaxially anisotropic medium. The second method is based on the use of the Azzam Universal Relationship (AUR) between the Fresnel s- and p- reflection coefficients. For a flat surface and an isotropic medium, the Azzam combination of coefficients becomes zero and thus independent of the incidence angle. Finally, for those cases in which the anisotropy of the material of a film deposited on an isotropic substrate is itself of interest a third Interference Method (IM) is suggested. This technique makes use of the different dependences of s- and p- polarized beam optical pathlength changes on the variation of the angle of incidence.
Microscopic symmetry of ordered media (crystals) manifests itself in an anisotropy of the refractive index. Whereas the internal structure of radiators is taken into account by multipolar expansion, neither radiator size nor lattice grain size ever enters into formulas for the refractive index n of a medium. In optics such an approach is usually well-grounded because of the smallness of these sizes compared with the wavelength (lambda) . Thus, according to the classical Lorentz- Lorenz (LL) formula, the optical properties of an isotropic medium depend merely on the product of a density N of the radiators and the polarizability (alpha) of an isolated radiator. Under derivation of LL formula one assumes the well- known generally accepted connection between a local field vector E' which acts on a separate radiator and mean macroscopic (Maxwell) field vector E:vector E' equals vector E + 4(pi) /3 vector P, where vector P is the mean polarization of a medium. We will show that this relation holds true only for a linear isotropic medium in zeroth (in the medium's discrete parameter) approximation and will derive general relation for arbitrary nonlinear and anisotropic medium with account of its discreetness. It quite naturally leads to modification of LL relation as well.
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