Photon-photon interactions via Rydberg blockade

We develop the theory of light propagation under the conditions of electromagnetically induced transparency in systems involving strongly interacting Rydberg states. Taking into account the quantum nature and the spatial propagation of light, we analyze interactions involving few-photon pulses. We show that this system can be used for the generation of nonclassical states of light including trains of single photons with an avoided volume between them, for implementing photon-photon gates, as well as for studying many-body phenomena with strongly correlated photons.     

Elastic scattering of 86 MeV9Li and 55 MeV6He on208Pb

The cross sections of elastically scattered⁹Li and⁶He on²⁰⁸Pb were measured. The scattered particles were detected by an annular CR-39 solid state nuclear track detector and the monitoring was done with a triple telescope of silicon detectors. The classical and optical model analyses of the measured elastic cross sections have been carried out. It was shown that the peripheral⁹Li interaction region has a rather high transparency. Strong dynamical polarization of⁹Li ions in the process of scattering is suggested.     

Solid solubility in the Bi-Sb-As ternary system

The existence region of the ternary solid solution in the Bi-Sb-As system is studied using DTA, X-ray powder diffraction, and thermodynamic calculations. The alloys of this system have positive nonideality, which is mainly due to the elastic component of the enthalpy of mixing. The nonideality increases as the antimony concentration in the sample decreases, and finally brings about the instability and decay of the solid solution. It is shown experimentally that complete miscibility is observed at high antimony concentrations, when the antimony atom fraction is higher than or equal to 0.75–0.80.     

Polarization of radiation under superradiance conditions

A theoretical study is made of the polarization properties of superradiance emitted by gases in a high-current longitudinal discharge. It is shown that the Zeeman effect in the discharge current makes the radiation at the periphery of a light beam totally polarized. Formulas are derived for relating the degree of polarization of a light beam with the dependences of the gain profile on the frequency and on the transverse coordinate. An analysis is made of the influence of diffraction on the polarization properties of a light beam and the anisotropic waveguide modes are found. A calculation is made of the distribution of the intensity of the optical field when radiation is generated between crossed Polaroids at the exit end of the discharge tube.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 51–56, May, 1980.The authors are grateful to A. I. Odintsov and V. P. Yakunin for frequent discussions.     

Superheavy hydrogen 5H and spectroscopy of 7He

Data on the spectroscopy of ⁵H and ⁷He from recent experiments with radioactive beams in Dubna and in RIKEN are presented.     

Complexes of technetium(I) (Tc, Tc) pentacarbonyl core with π-acceptor ligands (tert-butyl isocyanide and triphenylphosphine): Crystal structures of [Tc(CO)5(PPh3)]OTf and [Tc(CO)5(CNC(CH3)3)]ClO4

A procedure was developed for preparing [^99mTcX(CO)₅] (X = Cl, Br, I) in a reasonable yield by high-pressure carbonylation with CO of ^99mTcO₄⁻ in aqueous solutions. In the synthesis, the substantial part of the target product is accumulated in the gas phase and can be transferred from the autoclave into various solvents when relieving the pressure. Compounds [^99mTcX(CO)₅] (X = Cl⁻, Br⁻, I⁻) are stable in solutions for several hours, but in the course of longer storage they gradually decompose to give the tricarbonyl species. Substitution of the halide ligands in [⁹⁹TcX(CO)₅] and [^99mTcX(CO)₅] with tert-butyl isocyanide and triphenylphosphine was studied. The structures of the complexes [Tc(CO)₅(PPh₃)]OTf and [Tc(CO)₅(CNC(CH₃)₃)]ClO₄ are presented.     

Limiting shear stress and monotonic properties of liquid water

Technical Physics - Publications in scientific journals in which the authors attempt to experimentally prove that water, the most widespread substance on the Earth, is not a completely classical...     

Size-exclusion liquid chromatography of poly(<Emphasis Type="Italic">N</Emphasis>-vinylformamide)s in aqueous solutions

The exclusion mechanism of the separation of poly(N-vinylformamide) and its derivatives with a cysteamine terminal group in gel permeation chromatography implemented by the suppression of polyelectrolyte swelling and the electroexclusion of macromolecules was established by the transport analytical methods of molecular hydrodynamics (HPLC, velocity sedimentation, and intrinsic viscosity). Based on an analysis of the hydrodynamic characteristics and molecular weights of polymer fractions determined by velocity sedimentation, it was found that the molecular characteristics and polydispersity of the water-soluble poly(N-vinylamide) s of aliphatic carboxylic acids and their derivatives can be calculated with the use of the Benoit universal calibration dependence.