The structure and potentials of the interaction of complexes of polyatomic anions with Li, Na, and the molecules of aprotic solvents

The semiempiric CNDO method with the modified potential of core-core repulsion is used for quantum-chemical calculations of the potential surface cross-sections, charge distribution and the electrostatic field in complexes of the type A⁻…M⁺ (A⁻ = ClO⁻₄, NO⁻₃, SCN⁻, BF⁻₄, AsF⁻₆; M⁺ = Li⁺, Na⁺) and A⁻…M⁺…Mol (acetonitrile, pyridine, dimethylformamide, dimethylsufloxide, nitromethane, tetrahydrofuran). It is established that the anion-cation interaction potential has the form of a complex function with several minima which correspond to possible types of coordination between anions and cations. The effect of solvent molecules leads to the weakening of the interionic bond and the decrease of the potential barrier between configurations with different types of anion-cation coordination.     

Laser synthesis of metal–metaloxide nanoparticles on carbonic materials in an electric field

Nanoparticles of palladium and its oxides are synthesized on carbonic materials via the laser ablation and deposition of metals in electric fields. Studies of the materials show it is possible to control the crystallinity, size, and chemical state of nanoparticles without changing the laser beam parameters.     

The pump-probe approach to coherent backscattering of intense laser light from cold atoms

We present a new approach to near-resonant coherent backscattering of light from cold two-level atoms. In the dilute regime, where the distance between atoms is much larger than the laser wavelength, this approach is able to account for multi-photon scattering processes between many atoms through solutions of single-atom optical Bloch equations. We elaborate the method for double scattering from two atoms, and discuss the way of its extension for dilute, cold atomic clouds.     

Estimation of crystal sample structure by means of fast electron radiation

The dependence of the characteristics of X-ray radiation occurring under fast electron transmission through a crystal on a sample structure has been analyzed. A method to estimate the size of the crystal microblocks by means of the yield ratio of the parametric X-ray radiation and diffracted bremsstrahlung and transition radiation for different observation angles has been suggested. The possibility of estimating the dimension of the microblocks using the ratio of the intensities of these emission mechanisms for the same observation angle and several reflection orders has been discussed.     

Conceptual Design of a Dedicated Fourth-Generation Specialized Synchrotron Radiation Source (SSRS-4) at the Kurchatov Institute

Physics of Atomic Nuclei - Work on the conceptual design of a dedicated fourth-generation fourth-generation Specialized Synchrotron Radiation Source (SSRS-4) is in progress at the Kurchatov...     

Spectral detection of resonance fluorescence as a generalized quantum measurement

Spectrally resolved detection of single atom resonance fluorescence in the limit of well-separated spectral lines is considered. By using a special type of correlation measurements over the fluorescent field, in which a filtered photon detection is followed by an unfiltered photon detection, we obtain a conditioned atomic state following the filtered photon detection. The properties of the atomic state following detection of the reflected photon are studied and interpreted on the basis of quantum interference between the dressed states. Measurement operators associated with the detection of the passed and reflected photons are derived and used to construct the master equation for the atomic density matrix subjected to continuous spectral detection, the filter tuning being arbitrary.     

Atomic state reduction and energy balance relation in spectrally resolved resonance fluorescence

The paper is devoted to a study of properties of the reduced atomic state directly after detection of a resonance fluorescence photon that passed through a spectral (Fabry–Perot) filter. We establish the energy balance relation for the reduced state and discuss its observable consequences.     

Spatial spin-modulated structure and hyperfine interactions of 57Fe nuclei in multiferroics BiFe1–x T x O3 (T = Sc,Mn; x = 0, 0.05)

The results of the Mössbauer studies on ⁵⁷Fe nuclei in multiferroics BiFe_1–x T _x O₃ (T = Sc, Mn; x = 0, 0.05) in the temperature range of 5.2–300 K have been presented. The Mössbauer spectra have been analyzed in terms of the model of an incommensurate spatial spin-modulated structure of cycloid type. Information has been obtained about the effect of the substitution of Sc and Mn atoms for Fe atoms on the hyperfine parameters of the spectrum: the shift and the quadrupole shift of the Mössbauer line, the isotropic and anisotropic contributions to the hyperfine magnetic field, and also the parameter of anharmonicity of the spatial spin-modulated structure.