S.N. Ivanov

Station for VUV-spectroscopy at beam line M of the storage ring Siberia-I

Abstract The station for solid state VUV-spectroscopy on the dedicated SR source Siberia-I of the Kurchatov Institute, USSR, is described. The station consists of a beam line, vacuum normal-incidence primary Wadsworth monochromator, sample chamber, secondary monochromator and a computer control system. Characteristics of the optical scheme are discussed. The experimental procedure in the VUV range is described.

Time resolved luminescence spectroscopy of wide bandgap insulators

This is a review of the recent activity of a collaboration on the basis of an INTAS grant ‘The luminescence process — a study of the excitation and radiation dynamics of materials using synchrotron radiation’. For the following crystals (CeF3, LaF3:Ce, PWO, LSO:Ce, CsI, RbI, KI, CsF, CsCl, BaF2, CsPbCl3, etc.) in the UV, VUV, XUV, and X-ray regions the sequential steps of the energy conversion of a high-energy photon into a luminescence quantum have been studied: (i) absorption; (ii) multiplication of electronic excitations; (iii) migration in the process of thermalisation; (iv) emission center excitation.

A station for VUV spectroscopy with the Seya-Namioka monochromator at the Siberia-1 storage ring

Abstract The station for solid-state VUV spectroscopy on the dedicated SR source Siberia-1 of the Kurchatov Institute, USSR, is described. The station consists of a beam line, a Seya-Namioka monochromator with toroidal focusing mirrors, a high-vacuum sample chamber and a computer control system. Characteristics of the optical scheme are discussed.

Optical and luminescent VUV spectroscopy using synchrotron radiation

The main processes of energy relaxation occurring in solids upon high-energy excitation are described, and the information that can be obtained by vacuum ultraviolet (VUV) spectroscopy for each relaxation stage is presented. The theoretical and experimental results obtained by the authors using synchrotron radiation are reported.

Luminescence excitation and its relation to the structures of natural crystalline diamond and diamond-like films

The luminescence excitation spectra (LES) of natural crystalline diamond and amorphous diamond-like films are measured at energies from 4 to 20 eV at the LOCUS station for luminescence and optical studies of the Kurchatov Institute synchrotron radiation source. Two sharp peaks at 5.5 and 10.5 eV are observed in the LES of diamond, while the LES of the film demonstrate only one peak at 10.5 eV. For crystalline diamond, the peaks can be explained within the framework of the diamond band structure and the processes of inelastic scattering of photoexcited holes. Dark-field electron microscope images of the diamond-like film show that, in spite of its amorphous structure, this film contains regions of coherent electron scattering whose dimensions are on the order of 2–5 nm, which is sufficient to describe the film LES using a model for crystalline diamond. The absence of the first peak in the film LES is related to the fact that the absorption coefficient of diamond is very small at 5.5 eV and radiation is only slightly absorbed by the thin film.

High‐luminosity system for XEOL spectroscopy (abstract)

A high‐luminosity system comprising optically matched sample chamber, monochromator‐spectrograph, and detectors of luminescences has been designed for XEOL spectroscopy using synchrotron radiation. Exciting x‐ray radiation penetrated the sample chamber through a window made of a Be foil. The sample is mounted on the sample holder of a nitrogen cryostat. The entrance slit of the monochromator is fixed on the sample’s surface. Luminescence is excited and detected at the same side of the sample and optical slit; the angle between the exciting radiation and the entrance shoulder of the monochromator is 45°. Sample chamber has two windows made of a Be foil for incident and transmitted x‐ray radiation and another one made of MgF2 for outcoming luminescence. A Seya–Namioka mounting with 70.5° has been chosen for the spectra instrument as it is characterized by a flat field in the focal surface in the area of the exit slit, providing the possibility to detect luminescence either in the mode of a monochromator or ...

Spontaneous-induced parametrical scattering: applications using synchrotron radiation

The absolute method (AM) of brightness determination based on the comparison of the brightness measured and that of zero fluctuations of electro-magnetic vacuum in the process of parametrical scattering of light, gives rise to new possibilities for synchrotron radiation brightness. Another possibility is the use of AM together with the properties of synchrotron radiation for unique determination of fine structure constant not applying any numerical constants or standards.