Circular and near-circular polarization states of evanescent monochromatic light fields in total internal reflection

Conditions for the production of near-circular polarization states of the evanescent field present in the rarer medium in total internal reflection of incident monochromatic p-polarized light at a dielectric-dielectric planar interface are determined. Such conditions are satisfied if high-index (\u3e3.2) transparent prism materials (e.g., GaP and Ge) are used at angles of incidence well above the critical angle but sufficiently below grazing incidence. Furthermore, elliptical polarization of incident light with nonzero p and s components can be tailored to cause circular polarization of the resultant tangential electric field in the plane of the interface or circular polarization of the transverse electric field in a plane normal to the direction of propagation of the evanescent wave. Such polarization control of the evanescent field is significant, e.g., in the fluorescent excitation of molecules adsorbed at solid-liquid and solid-gas interfaces by total internal reflection

Circular and near-circular polarization states of evanescent monochromatic light fields in total internal reflection

Conditions for the production of near-circular polarization states of the evanescent field present in the rarer medium in total internal reflection of incident monochromatic p-polarized light at a dielectric-dielectric planar interface are determined. Such conditions are satisfied if high-index (\u3e3.2) transparent prism materials (e.g., GaP and Ge) are used at angles of incidence well above the critical angle but sufficiently below grazing incidence. Furthermore, elliptical polarization of incident light with nonzero p and s components can be tailored to cause circular polarization of the resultant tangential electric field in the plane of the interface or circular polarization of the transverse electric field in a plane normal to the direction of propagation of the evanescent wave. Such polarization control of the evanescent field is significant, e.g., in the fluorescent excitation of molecules adsorbed at solid-liquid and solid-gas interfaces by total internal reflection

Market Power and/or Efficiency: An Application to U.S. Food Processing

This article separates oligopoly-power and cost-efficiency effects of changes in industrial concentration and assesses their impact on output prices in 32 food-processing industries. Empirical results indicate that although concentration induces cost efficiency in one-third of the industries, oligopoly-power effects either dominate cost efficiency or reinforce inefficiency, resulting in higher output prices in most industries. The article also provides fresh econometric estimates of oligopoly power and economies of size for the industries in question.industrial concentration, economies of scale, industrial organization, oligopoly power, food processing, Agribusiness, Industrial Organization, Productivity Analysis, L00, L11, L13, L66,

New type of ellipsometry in infrared spectroscopy: The double-reference method

We have developed a conceptually new type of ellipsometry which allows the determination of the complex refractive index by simultaneously measuring the unpolarized normal-incidence reflectivity relative to the vacuum and to another reference media. From these two quantities the complex optical response can be directly obtained without Kramers-Kronig transformation. Due to its transparency and large refractive index over a broad range of the spectrum, from the far-infrared to the soft ultraviolet region, diamond can be ideally used as a second reference. The experimental arrangement is rather simple compared to other ellipsometric techniques.Comment: submitted to Appl. Phys. Let

Application of the Ninhydrin and Alloxan Reactions to Tissue Sections

The ninhydrin and alloxan reactions have been criticized as being nonspecific and unreliable for histochemical studies due to the diffusion, solubility, and fading of their reaction products. This paper presents some modifications of the techniques that appear to render the reactions more reliable for the identification of proteins and peptides possessing terminal α-amino acids. The resulting color complexes are also stable

Extreme ultraviolet polarizing optics using bare and aluminum-coated silicon carbide

A deformable three-reflection system that uses a bare silicon carbide substrate can function as an in-line, high-throughput (\u3e30%), 90° phase shifter in the 50–100 nm spectral range. For a given extreme ultraviolet wavelength, an aluminum thin film can be deposited on the silicon carbide substrate to suppress the parallel (p) or perpendicular (s) polarization on single reflection or to introduce quarter-wave retardation and equal reflectances for incident p- and s-polarized light

Constraint on the optical constants of a transparent film on an absorbing substrate for inversion of the ratio of complex p and s reflection coefficients at a given angle of incidence

An absorbing substrate of complex refractive index n2-jk2 can be coated by a transparent thin film of refractive index n1 and normalized thickness ζ so that the ratio of complex reflection coefficients for the pand s polarizations of the film-covered substrate ρ is the inverse of that of the film-free substrate ρ¯ at a given angle of incidence φ. A pair of parallel (metallic) mirrors, one uncoated and the other coated with a ρ-inverting layer, causes a beam displacement without change of polarization and with a certain net reflectance (insertion loss) ℜ. In this paper the constraint on n1,n2,k2 for ρ inversion (ρρ¯ = 1) is represented by a family of constant -n1 contours in the n2k2 plane at φ = 45, 60, and 75°. Along each solution curve, ζ and ℜ are also plottedvs n2 at constant n1. Analysis of the effect of small errors of incidence angles, film refractive index, and thickness is presented for two specific designs using Al mirrors at 650 and 950 nm

Extreme ultraviolet polarizing optics using bare and aluminum-coated silicon carbide

A deformable three-reflection system that uses a bare silicon carbide substrate can function as an in-line, high-throughput (\u3e30%), 90° phase shifter in the 50–100 nm spectral range. For a given extreme ultraviolet wavelength, an aluminum thin film can be deposited on the silicon carbide substrate to suppress the parallel (p) or perpendicular (s) polarization on single reflection or to introduce quarter-wave retardation and equal reflectances for incident p- and s-polarized light

Constraint on the optical constants of a transparent film on an absorbing substrate for inversion of the ratio of complex p and s reflection coefficients at a given angle of incidence

An absorbing substrate of complex refractive index n2-jk2 can be coated by a transparent thin film of refractive index n1 and normalized thickness ζ so that the ratio of complex reflection coefficients for the pand s polarizations of the film-covered substrate ρ is the inverse of that of the film-free substrate ρ¯ at a given angle of incidence φ. A pair of parallel (metallic) mirrors, one uncoated and the other coated with a ρ-inverting layer, causes a beam displacement without change of polarization and with a certain net reflectance (insertion loss) ℜ. In this paper the constraint on n1,n2,k2 for ρ inversion (ρρ¯ = 1) is represented by a family of constant -n1 contours in the n2k2 plane at φ = 45, 60, and 75°. Along each solution curve, ζ and ℜ are also plottedvs n2 at constant n1. Analysis of the effect of small errors of incidence angles, film refractive index, and thickness is presented for two specific designs using Al mirrors at 650 and 950 nm