Selective laser spectroscopy of molecules in matrices. Experiments with porphyrins

A review is presented of experiments on selective laser excitation of luminescence and hole burning in the absorption spectra of porphyrins in amorphous matrices at liquid helium temperatures.Division of Quantum Radiophysics, Lebedev Physics Institute, Academy ofSciences of the USSR, Moscow. Translated from Preprint No. 165 of the Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1988.     

Kinetics of photochemical hole burning in the absorption spectra of molecules in matrices

The relation between the homogeneous absorption spectrum of impurity centers and the hole photochemically burned by monochromatic laser radiation in an inhomogeneous absorption spectrum is studied. The changes, due to the burning, of the zero-phonon is studied. The changes, due to the burning, of the zero-phonon hole contour are analytically calculated for any ratio of the laser and the zero-phonon lines. The model calculations are confirmed by experiments with the protoporphyrin dictation in an amorphous matrix at helium temperature.Quantum Radiophysics Division, Lebedev Physics Institute. Translated from Preprint No. 79, Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1989.     

Photon-number oscillations in correlated light

Equations are derived, and numerical calculations performed, for the photon distribution function in correlated and squeezed light. It is shown that the distribution function oscillates as a function of the correlation and squeezing coefficients. The connection with experiments on photon counting is discussed.Translated from Preprint No. 178 of the Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1988.     

Faraday-rotation method for magnetic-field diagnostics in a laser plasma

The possibility of using the Faraday effect for the diagnostics of magnetic fields in a dense plasma is theoretically demonstrated. A procedure for measuring the plane of polariztion of the probing radiation is examined in detail, with account taken of the wave polarization and of the presence of plasma self-luminosity. A procedure for determining the spatial distribution of the magnetic field is described. A new three-channel polarointerferometer scheme is proposed. The idea behind the method is illustrated with reconstruction of the magnetic fields in a laser plasma as an example.Laser-Plasma Laboratory, Lebdev Physics Institute. Translated from Preprint No. 135 of the Lebedev Institute of Physics, Academy of Sciences of the USSR, Moscow, 1989.     

Analogy between mechanics and optics

Division of Theoretical Physics, Lebedev Physics Institute. Translated from Preprint 114, Lebedev Physics Institute, Moscow, 1990.     

Nonclassical transport in a nonequilibrium laser plasma

The onset of a nonequilibrium distribution function in a plasma produced by laser radiation at fluxes I - 10¹⁴ W/cm² is considered. The model employed takes consistent account of the nonlocality of the electron distribution at large density and temperature gradients, the demaxwellizing effect of the external hf field of the laser, and the nondiffusion of the transport in the high-energy part of the electron-distribution spectrum. Numerical solution of the corresponding kinetic equations shows that establishment of a nonequilibrium electron distribution in the corona suppresses the heat transport substantially. Good agreement is obtained between the kinetic value of the heat flux and the phenomenological value needed to reconcile the hydrodynamicsimulation results with the experimental data.Quantum Radiophysics Division, Lebedev Physics Institute. Translated from Preprint No. 179 of the Ledebev Physics Institute, Academy of Sciences of the USSR, Moscow, 1989.     

System for nanosecond and picosecond laser synchronization using high-voltage semiconductor switches

Results are presented on the development and investigation of a system for the synchronization of the emission of a nanosecond laser, used for plasma heating, with the emission of a diagnostic picosecond laser. The system is based on the use of the fast-semiconductor-switch technology, and ensures a temporal synchronization instability not higher than 100 psec.Laser-Plansma Laboratory and Special Design Office. Lebedev Physics Institutes, Academy of Sciences of the USSR. Translated from Preprint No. 85 of the Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1988.     

Correlated states of a quantum oscillator and of a quantum chain of oscillators with a δ bump in frequency

Quantum Radiophysics Division, Lebedev Physics Institute. Translated from Preprint No. 139 of the Lebedev Physics Institute, Russian Academy of Sciences, Moscow, 1991.     

USE of negative feedback to suppress injection-laser power fluctuation

P. N. Lebedev Physics Institute. Translated from Preprint No. 215 of the Lebedev Institute of Physics, Academy of Sciences of the USSR, Moscow, 1989.     

Anisotropy of Isobaric Instability in a Partially Ionized Plasma in a Magnetic Field

Bulletin of the Lebedev Physics Institute - Linear equations describing the dynamics of small perturbations in partially ionized heat-releasing plasma in an external magnetic field with an...     

Theory of spatiotemporal characteristics of laser emission. IV. Methods of controlling the spatial structures of laser beams in linear and nonlinear media

Part IV of the study continues the treatment of the theory of formation of laser beams with smooth spatial distribution, and of their conservation as they are transported in linear and nonlinear media. An exact solution is obtained for the problem of development of a small perturbation with an arbitrary amplitudephase distribution against the background of a plane wave with cubic nonlinearity. Self-consistent (waveguide) solutions of the nonlinear parabolic equation are obtained. The solutions demonstrate the effectiveness of suppression of small-scale self-focusing of diverging beams. The project of a high-aperture single-lens objective with aberration correction is developed and the relevant calculations are made.Quantum Radiophysics Division, Lebedev Physics Institute. Translated from Preprint No. 94 of the Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1990.     

Theoretical and numerical analysis of stresses in a laser hardening model

Kuibyshev Branch of the Lebedev Physics Institute. Translated from Preprint No. 167 of the Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1990.     

Coupling an injection laser to a single-mode optical fiberguide with the aid of a microlens in a matching-module system

Optoelectronics Laboratory, Lebedev Physics Institute. Translated from Preprint No. 192 of the Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1989.     

Relation between particle sizes and concentration in undiluted and diluted blood plasma according to light scattering data

Bulletin of the Lebedev Physics Institute - The article is devoted to the study of dilution effect on the blood plasma particle concentrations and sizes, obtained by dynamic light scattering...     

Review of methods of calculating the field in optical cavities and choice of calculation method for free-flow chemical lasers

Optics Division, Lebedev Physics Institute. Translated from Preprint No. 127 of the Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1990.     

Spatiotemporal characteristics of laser emission. III. Propagation of electromagnetic radiation beam in laser installations with allowance for large-angle diffraction and spatial self-focusing

In parts 1 and 2, the electrodynamic theory developed for the laser as a nonstationary nonlinear oscillating system with spatially distributed parameters was applied to specific laser types. The subject of part 3 is designated in the title.Division of Quantum Radiophysics, Lebedev Physics Institute. Translated from Preprint No. 86 of the Lebedev Physics Institute, Moscow, 1990.     

Analysis of low-frequency fluctuation of the radiation power of injection lasers

Quantum Radiophysics Division, Lebedev Physics Institute, Academy of Sciences of the USSR. Translated from Preprint No. 106 of the Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1989.     

Squeezed states of electromagnetic field

Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow. Translated from Preprint No. 232 of the Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1988.     

Some Features of Current Sheets Formed in Plasmas with Ions of Different Mass

Bulletin of the Lebedev Physics Institute - Abstract—Structural features of current sheets formed in laboratory experiments in plasma with ions of different mass are compared based on...     

STUDY OF PROPERTIES OF LASER-INDUCED PLASMA CHANNELS FODMED BY FEMTOSECOND LASER RADIATION

Bulletin of the Lebedev Physics Institute - Abstract—Laser-induced plasma channels (LIPC) formed during the interaction of ultrashort laser pulses with argon are studied. LIPC characteristics...