A brief review is given of lectures and papers presented at the Second International School on Coherent Optics and Holography, held in Varna in 1981. The proceedings were divided into the following sessions: fiber optics, integrated optics, holography and optical data processing.
M F Bukhenskiĭ and A S Semenov 1982 Sov. J. Quantum Electron. 12 820
M V Danileĭko et al 1982 Sov. J. Quantum Electron. 12 536
An experimental investigation was made of the influence of a controlled frequency nonreciprocity on the positions of phase resonances in ring lasers. An anomalously large shift of the phase resonances occurred as a result of a change in the frequency nonreciprocity of the resonator. It was found that an asymmetric position of a phase resonance relative to the edges of a single-wave generation zone could not be explained by an accidental frequency nonreciprocity of the laser resonator.
1975 Sov. J. Quantum Electron. 5 1455
V É Pozhar and V I Pustovoĭ 1987 Sov. J. Quantum Electron. 17 509
An analysis is made of the reduction in the duration (compression) of picosecond light pulses as a result of collinear Bragg diffraction on a phase grating induced in a crystal by an ultrasonic wave with linear frequency modulation. It is shown that an acoustooptic dispersive component utilizing this compression principle has the advantages of tunability and a fairly high energy efficiency.
S B Papernyĭ et al 1983 Sov. J. Quantum Electron. 13 293
Measurements were made of the dependences of the stimulated Brillouin scattering (STBS) threshold and of the gain g (cm/MW) on the pressure of argon. The influence of the focusing geometry on the process of competition between STBS and optical breakdown was studied. The influence of breakdown on STBS was described by introducing effective nonlinear losses proportional to the intensity of the pump radiation. Within the framework of this approach a good agreement was obtained between the experimental and theoretical results.
R Altynbaev et al 1979 Sov. J. Quantum Electron. 9 1435
The characteristics of heterojunction lasers and light-emitting diodes grown on n- and p-type substrates in a four-component InGaPAs solid solution were compared. Investigations were made of the spectral, temporal, power, and radiative characteristics. The temperature dependence of the threshold current of a heterojunction laser (1.07 μ, 300°K) was compared with the corresponding dependence of an InP homojunction laser. Stimulated emission at λ = 1.19 μ was obtained from an InP–lnGaPAs system at room temperature.
B I Vasil'ev et al 1977 Sov. J. Quantum Electron. 7 1027
An investigation was made of the energy, temporal, and spatial characteristics of an NH3 laser emitting at wavelengths 12.08 and 12.81 μ. An improved optical system and optimization of the operation of the NH3 laser made it possible to obtain an energy of 0.35 J per pulse. The peak output power of this laser was ≈0.5 MW and its efficiency was ≈8%.
É A Arutynyan et al 1975 Sov. J. Quantum Electron. 5 985
An investigation was made of the spectral characteristics of an LiNbO3 crystal which converted infrared radiation to the visible range by summing the infrared and ruby (pump) Irser frequf icies. The dependences of the spectral width of the conversion band on the pump line width and on the angle of divergence of the infrared radiation in the crystal were determined experimentally. The results were compared with theoretical estimates.
Yu A Bykovskiĭ et al 1978 Sov. J. Quantum Electron. 8 1297
A review is given of the literature on the interaction and conversion of surface waves in integrated-optics elements with distributed coupling. A general description is given of the distributed coupling of surface waves in thin-film waveguides and a detailed investigation is made of their interaction and conversion in waveguides with periodically modulated parameters. The different types of periodic modulation of the parameters of thin-film waveguides are discussed and compared. The main elements and devices in integrated-optics systems based on periodic diffraction-grating structures are examined. The possibility of using "aperiodic" grating structures in integrated optics is demonstrated and devices with tunnel distributed coupling are considered.
V V Ryzhov and A G Yastremskiĭ 1979 Sov. J. Quantum Electron. 9 1188
Solutions are obtained of the rate equations describing the processes in the plasma of excimer lasers utilizing rare-gas halide molecules. Formulas are obtained for estimating the efficiency of such lasers excited by an electron beam. Numerical simulation of the processes in excimer lasers shows that such formulas can be used to calculate the efficiency at gas pressures from 1 to 10 atm. The results are given of calculations of the maximum efficiency of KrF*, XeCl*, and XeBr* lasers.
A I Zagumennyĭ et al 1992 Sov. J. Quantum Electron. 22 1071
Single crystals of gadolinium vanadate doped with neodymium ions have been grown by the Czochralski method. The absorption and luminescence spectra of the neodymium have been measured. The absorption near 0.8 μm is higher than 70 cm−1. The lifetime of the neodymium ions is 90 μs. Laser action has been achieved on the transitions 4F3/2 → 4I13/2, 4I11/2. The differential efficiency of the lasing near 1.06 μm is 54%.
O V Angel'skiĭ 1992 Sov. J. Quantum Electron. 22 1073
This review examines some questions concerning the capabilities of interference and polarization-interference correlation diagnostics of the amplitude-phase characteristics of random optical fields for the purpose of identifying these fields and then studying the corresponding objects. The diagnostics of random phase objects is discussed separately in the cases in which the phase dispersion of the inhomogeneities is less than and greater than one. The outlook is promising for the use of the correlation dimensionality of chaos in a field as a diagnostic parameter. It is also shown that the use of interference principles for a parallel processing of large data files can substantially increase the speed of processing systems.
V L Kalashnikov et al 1992 Sov. J. Quantum Electron. 22 1081
It is predicted theoretically that the efficiency of self-mode locking can be raised by means of a bleachable shutter in the main cavity or an auxiliary cavity. The laser emits a stable train of ultrashort pulses under these conditions. The theory is based on a fluctuation model of the operation of a cw solid-state laser with a linear auxiliary cavity. The increase in efficiency involves a broadening of the region of parameter values of the system in which self-mode locking occurs, a significant decrease in the threshold pump intensity, and a reduced sensitivity of the operation to the phase mismatch of the lengths of the cavities. It is shown, for the first time, that a stable train of double ultrashort pulses can be generated by a system with a shutter in the auxiliary cavity. It is also shown that a self-mode locking is possible in the case in which there is a phase mismatch of the cavity lengths and there is no phase self-modulation in the main cavity.
Aleksandr E Obukhov 1992 Sov. J. Quantum Electron. 22 1086
The photophysical properties of some new and also some known complex organic molecules which emit in the wavelength interval 340–410 nm have been studied in a wide range of organic solvents. Specifically, these molecules are based on phenyl-, furyl-, and thienyl-oxazoles and oxadiazoles. Density-matrix methods are used to study the properties of a broad spectrum of excited singlet and triplet electronic states. There are relationships among the structure, fluorescence spectra, and emission properties of the complex molecules forming a quasihomologous series. The method of a priori structural modeling of active complex molecules is useful for achieving quantum-mechanical control over the properties of the excited states and the transitions.
A M Boĭchenko and Sergei I Yakovlenko 1992 Sov. J. Quantum Electron. 22 1094
The anomalous emission (λ~146 nm) from a Kr–Xe mixture observed in a previous study is interpreted as emission in the course of optical collisions. A kinematic model is constructed which explains the dependence of the emission intensity on the composition and temperature of the gas mixture.
O V Angel'skiĭ 1992 Sov. J. Quantum Electron. 22 1073
This review examines some questions concerning the capabilities of interference and polarization-interference correlation diagnostics of the amplitude-phase characteristics of random optical fields for the purpose of identifying these fields and then studying the corresponding objects. The diagnostics of random phase objects is discussed separately in the cases in which the phase dispersion of the inhomogeneities is less than and greater than one. The outlook is promising for the use of the correlation dimensionality of chaos in a field as a diagnostic parameter. It is also shown that the use of interference principles for a parallel processing of large data files can substantially increase the speed of processing systems.
S Nakai et al 1992 Sov. J. Quantum Electron. 22 881
A A Zozulya 1992 Sov. J. Quantum Electron. 22 677
A review is given of theoretical and experimental investigations of the role of the fanning in the operation of self-pumped four-wave mixing systems. It is shown that in some cases the fanning determines the dynamics of such systems and their final steady states.
B N Morozov 1992 Sov. J. Quantum Electron. 22 541
A brief review is given of the characteristics of possible methods for stabilizing the energy parameters of laser radiation. Attention is drawn to the possibility of stabilizing the laser radiation power by optical rectification. Three possible stabilization systems are suggested and methods are identified for arranging crystals in the crystal capacitors needed in this case.
Igor' M Bel'dyugin et al 1992 Sov. J. Quantum Electron. 22 384
The results are given of recent investigations of the feasibility of using photorefractive crystals in the construction of optical neural computers and of associative memories. The physical basis of the interaction of laser radiation with photorefractive crystals is given and the principles governing the formation of an all-optical neuron and of links (synapses) between neurons in such crystals are discussed. An analysis is made of the learning capabilities of various models of neural networks (Boltzmann machine, perceptron, associatron, neural networks with competition, etc.) and optical systems implementing these models with the aid of photorefractive crystals are described. Extensive experimental data are reported and the results are given of modeling of various tasks (multidimensional optimization, image recognition, etc.) by optical neural computers.