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[en] Proceeding from the fundamentals a survey is given of the modern methods and experimental possibilities of optical spectroscopy, and of the application to solid state investigations. Contents: receiver, transmission of optical radiation, spectral analysis, polarization, radiation sources, arrangement and measurement. 58 figs., 12 tabs., 177 refs
[en] The generalized impedance spectroscopy is implemented through the detection of perturbations in the electromagnetic impedance of a medium measured at radiofrequencies. The perturbations are caused by the absorption or emission of optical photons. At low powers this offers an extremely high sensitivity spectroscopic technique, which is illustrated here for a two-photon absorption process. In the limit of high powers it becomes equivalent to optogalvanic spectroscopy with several important advantages. (authors)
[en] Status Update of the Precision Attenuation Length Measurement Setup The planned JUNO detector is a 20 kt liquid scintillator neutrino detector. Its primary goal is the determination of the neutrino mass hierarchy. This will be done by precision measurements of the reactor antineutrino survival probability. Due to the spherical detector's diameter of approx. 35.5 m, the optical parameters, especially the attenuation length, of the scintillator have to be known precisely and have to be very good to achieve the required energy resolution of 3% rate at 1MeV. To determine one of the crucial optical parameters, the attenuation length, a new spectrometer experiment, called PALM, was built. Unless the commercially available spectrometers with light paths up to 10 cm, this spectrometer is able to measure light paths up to 2.8 m through the medium, making it possible to determine the attenuation length very precisely. This talk gives a status update on the commissioned PALM setup.
[en] A unit of automatic control of discrete recording of spectrum in the DFS-24 spectrometer device used in the flowsheet of photon counting during monochannel digital accumulation has been described. Discrete regime of spectrum scanning can be used alongside with continuous one which can be ensured by the DFS-24 device
[en] We review recent advances in optical and magnetooptical (MO) scatterometry applied to periodically ordered nano structures such as periodically patterned lines, wires, dots, or holes. The techniques are based on spectroscopic ellipsometry (SE), either in the basic or generalized modes, Mueller matrix polarimetry, and MO spectroscopy mainly based on MO Kerr effect measurements. We briefly present experimental setups, commonly used theoretical approaches, and experimental results obtained by SE and MO spectroscopic analyses of various samples. The reviewed analyses are mainly related to monitoring optical critical dimensions such as the widths, depths, and periods of the patterned elements, their real shapes, and their line edge or linewidth roughness. We also discuss the advantages and disadvantages of the optical spectroscopic techniques compared to direct monitoring techniques.
[en] The refraction of rays in the Savart polariscope is different from the isotropic medium. We have analysed and discussed the refraction of rays in the Savart polariscope on the basis of the Snell law. The refraction formulae of the extraordinary rays and ordinary rays were derived. Results obtained may provide theoretical and practical guide lines for studying, developing and engineering of polarization interference imaging spectrometer. (classical areas of phenomenology)
[en] The present review reflects the importance of dielectric barrier discharges for optical spectrometric detection in analytical chemistry. In contrast to usual discharges with a direct current the electrodes are separated by at least one dielectric barrier. There are two main features of the dielectric barrier discharges: they can serve as dissociation and excitation devices as well as ionization sources, respectively. This article portrays various application fields of dielectric barrier discharges in analytical chemistry used for elemental and molecular detection with optical spectrometry. - Highlights: • Dielectric barrier discharges for optical spectrometric detection in analytical chemistry. • Electrodes are separated by at least one dielectric barrier. • A DBD can serve as dissociation and excitation device and as ionization source. • Various application fields of DBDs for elemental and molecular detection with optical spectrometry.
[en] The article gives a brief overview of the basic concepts of ellipsometry, the principle of operation and types of ellipsometers in order to promote the application of this optical method in materials science. Those readers who are interested in a deeper knowledge of the method can turn to the cited literature.
[en] Magnitudes of linear polarization in the UBVRI bands have been measured for about 30 background stars in the direction of the Chamaeleon I dark cloud. In addition, high-resolution spectroscopic observations in the wavelength ranges of the atomic species Ca II and Ca I and of the molecular species CH and CH+ have been performed towards the highly reddened and early-type stars selected from the polarimetry sample. The data have been used to study the magnetic-field structure, the relation between polarization and extinction, and the relation between molecular abundances and polarization properties in the cloud. In this contribution they present some of the results