Rogalin V.E.,Astrofizika Research and Production Association
Bulletin of the Russian Academy of Sciences: Physics | Year: 2012
Micropores up to 30-100 μm in size (bulk density ∼105 cm-3) are obtained in NaCl, KCl, KBr, and RbI via the effect of a pulse of a CO2 laser with power density 106-107 W cm-2 up to 5 μs long. When a pore appears, plasma formation is initiated. The average temperature is ∼5500 K and the pressure is ∼104 kg cm-2. The dependence of the average weight of the material removed from the pore on the energy of the crystal lattice is found. Pore formation occurs mainly via the effect of the radiation pulse, due to evaporation at the absorption wave front (velocity, 5 m s-1) and plastic deformation. The annealing kinetics of micropores and the effect of the ionizing radiation on the bulk pore formation in NaCl crystals are investigated. © 2012 Allerton Press, Inc.
Kutaev Y.F.,Astrofizika Research and Production Association |
Mankevich S.K.,Astrofizika Research and Production Association |
Nosach O.Y.,Russian Academy of Sciences |
Orlov E.P.,Russian Academy of Sciences
Acta Astronautica | Year: 2010
It is proposed to use the wavelength 1.315 μm of the laser transition 2P1/2→2P3/2 in atomic iodine both for passive and active SETI. The search for an extraterrestrial signal at this wavelength is promising because an active quantum filter (AQF) with a quantum sensitivity limit and with strong fixing in the spectrum luminescence line of the width less than 0.01 cm-1, has been developed for the noted wavelength. Such AQF is capable of receiving the laser signals, consisting of only a few photons, against the background of emission from a star under study. In addition, the high-energy iodine lasers emitting diffraction-limited nanosecond pulses of energy of 2 kJ in a single beam at the wavelength 1.315 μm have been created. The spectral tuning of radiation of these lasers allows one to compensate the frequency Doppler shift. A weak absorption of the 1.315 μm radiation in the Earth atmosphere allows the search for extraterrestrial signals by using the ground optical telescopes equipped with adaptive optical systems. © 2010 Elsevier Ltd. All rights reserved.
Andreev S.A.,Astrofizika Research and Production Association |
Andreeva N.P.,Astrofizika Research and Production Association |
Barashkov M.S.,Astrofizika Research and Production Association |
Badikov V.V.,Kuban State University |
And 12 more authors.
Quantum Electronics | Year: 2010
Different versions of optical parametric oscillator (OPO) schemes were experimentally realised and investigated, which utilise AgGaS2, LiNbO3, and HgGa2S4 single crystals as well as an Hg1-xCdxGa2S4 solid solution. The OPOs generate radiation in the 1.2-5.7-μm range and make use of different ways of output wavelength tuning, including fast wavelength tuning (in a time shorter than 0.1 ms) with the help of an acoustooptical deflector. The output spectral line was narrowed by means of an intracavity acoustooptical filter. An OPO for the visible range with an electrodynamic tuning to an arbitrary wavelength in this range in a time of 5 ms was implemented employing a BBO single crystal. © 2010 Kvantovaya Elektronika and Turpion Ltd.