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1.
V. M. Apatin V. O. Kompanets V. N. Lokhman N. -D. D. Ogurok D. G. Poydashev E. A. Ryabov S. V. Chekalin 《JETP Letters》2011,94(7):570-573
Intracluster reactions that are induced in (CF3I)
n
clusters by femtosecond ultraviolet radiation, including the reaction of the formation of the I2+ molecular ion, have been directly observed. It has been shown that there are two channels of the formation of I2+ ions with the characteristic times τ1 ≈ 1 ps and τ2 ≈ 7 ps. A model of these reactions has been proposed that is in good agreement with the experimental data. 相似文献
2.
V. M. Apatin V. N. Lokhman G. N. Makarov A. L. Malinovsky A. N. Petin D. G. Poidashev E. A. Ryabov 《JETP Letters》2016,103(6):425-430
The properties of a superconducting flux quantum bit (qubit) in the quasidispersive mode, where the frequency of a probe signal is lower than the qubit excitation frequency but is close to it, have been experimentally studied. It has been shown that all parameters of the qubit inductively coupled to a coplanar resonator can be determined at the single-frequency excitation from the analysis of the frequency responses of the transmission of the probe signal at the output of this resonator. Under the additional excitation of the qubit by the signal at the second harmonic of the cavity, resonance dips have been observed because of resonance between the probe signal and induced Rabi splitting. It has been shown that the positions of these dips are in good agreement with the parameters of the qubit that are obtained by analyzing the amplitude–frequency response within the width of the fundamental resonance frequency. 相似文献
3.
V. M. Apatin V. O. Kompanets V. N. Lokhman N. -D. D. Ogurok D. G. Poydashev E. A. Ryabov S. V. Chekalin 《Journal of Experimental and Theoretical Physics》2012,115(4):567-578
The excitation and ionization of CF3I molecules and their clusters by femtosecond UV laser pulses is studied. It is concluded that the types of excitation of free CF3I molecules and their clusters by femtosecond UV laser pulses are different. The composition and kinetic energy of ion products observed upon the ionization of (CF3I) n clusters by femtosecond pulses are found to differ considerably from those obtained upon ionization by nanosecond pulses. It is shown that the molecular I 2 + ion is produced in reactions induced in (CF3I) n clusters by UV radiation. Using the pump-probe method, we found the two channels of producing I 2 + ions with characteristic times ??1 ?? 1 ps and ??2 ?? 7 ps. A model of the reactions under study proposed in the paper is consistent with our experimental results. 相似文献
4.
V. M. Apatin V. N. Lokhman G. N. Makarov D. D. Ogurok A. N. Petin E. A. Ryabov 《JETP Letters》2013,97(12):697-703
The fragmentation of homogeneous (CF3I) n clusters (where n ≤ 45 is the average number of molecules in a cluster) in a molecular beam, as well as (CF3I) n clusters inside of large (Xe) m clusters (where m ≥ 100 is the average number of atoms in a cluster) or on their surface, by laser ultraviolet radiation has been studied. It has been found that the indicated three types of (CF3I) n clusters have different stabilities with respect to fragmentation and strongly different dependences of the fragmentation probability on the energy of ultraviolet radiation. Fragmentation at low energies and the weakest energy dependence of the probability of fragmentation are observed for homogeneous clusters, a stronger dependence is characteristic of (CF3I) n clusters localized inside (Xe) m clusters, and the strongest dependence is observed for (CF3I) n clusters on the surface of (Xe) m clusters. Possible reasons for such a character of the observed dependences have been discussed. 相似文献
5.
V. M. Apatin V. N. Lokhman G. N. Makarov N. -D. D. Ogurok E. A. Ryabov 《Journal of Experimental and Theoretical Physics》2017,124(4):531-539
The prebreakdown stage of a gas discharge in a diode with strongly overloaded cathode is studied by laser methods (by simultaneous use of multiframe interferometry and shadow and schlieren photographing) at atmospheric pressure. The spatial resolution of the methods is about 20 μm. A probing pulse of a laser (LS-2151 Nd: YAG laser with a half amplitude duration of 70 ps and a pulse energy of up to 40 mJ) is synchronized with a voltage pulse with accuracy of about 1 ns. High field strength at the cathode is achieved due to the use of thin individual metal tips on the electrodes. It is shown that the initial stage of breakdown of a discharge gap is accompanied by the emergence of a dense plasma cloud at the end of a tip with electron density of about 5 × 1019 cm–3 with a size of tens of microns, as well as by a sharp increase in the total current through the diode. After the emergence of a dense plasma cloud at the end of a cathode tip, a similar cloud is formed on the surface of the anode; sometime later, these clouds join together and form a tubular current channel. The dynamics of the breakdown, as well as the parameters of the plasma are studied by the abovementioned techniques in three independent optical channels. 相似文献
6.
The role of played by the intensity of the exciting TEA CO2 laser pulses in the processes of ir multiphoton absorption (MPA) of SF6 molecules cooled toT R?40 K andT v?160 K in a pulsed supersonic jet and the dissociation of SF6 in a bulk atT?300 K under essentially collisionless conditions have been investigated. A strong dependence of MPA and the dissociation yield on pulse intensity were observed. The frequency dependences of the intensity effects were studied. 相似文献
7.
The feasibility of obtaining highly enriched (up to 99.5%) carbon-13 by the method of isotopically selective IR multiple-photon dissociation (MPD) of Freon 22 (CF2HCl) molecules was studied for one- and two-stage schemes of the process in a laboratory apparatus with the intracavity location of a separation reactor. The concentration of 13C in the dissociation product C2F4 (tetrafluoroethylene) and the MPD yields were measured depending on the frequency and fluence of laser radiation, as well as on the Freon 22 pressure. At the irradiation geometry used, the concentrations of 13C up to 88% were obtained in the first stage of enrichment. The second enrichment stage was based on the isotope-selective dissociation of Freon 22 preliminarily enriched with 13C (up to 32.6%). After the second stage, the final 13C concentration of 99.5 ± 0.5% was attained in the product C2F4. 相似文献
8.
The multiple-photon absorption of pulsed TEA CO2 laser radiation by SF6 molecules cooled toT
R40K andT
v160K in the free jet expansion from a pulsed supersonic nozzle has been investigated at energy fluences of 0.1 to 3.0 J·cm–2.For practically all laser lines which coincide with the linear absorption spectrum of thev
3 vibrational mode of SF6 [P(12)...P(28), 10,6 m], the dependence of the absorbed energyE
ab on the exciting energy fluence was found to be steeper than linearE
abn, wheren=(1.1 to 1.8). Considerable increases of the absorption cross sections with increasing energy fluence were observed.The fraction of the molecules interacting with the laser radiation is estimated. 相似文献
9.
V. M. Apatin V. O. Kompanets V. B. Laptev Yu. A. Matveets E. A. Ryabov S. V. Chekalin V. S. Letokhov 《Russian Journal of Physical Chemistry B, Focus on Physics》2007,1(2):113-119
The effect of high-intensity femtosecond laser pulses (100–200 fs) in the near (0.8–1.8 μm) and medium (4.6–5.8 μm) IR ranges
on the CF2HCl, CF3H, (CF3)2C=C=O, and C4F9COI molecules is examined. Irradiation of CF2HCl and CF3H molecules by 0.8-to 1.8-μm laser pulses with intensities of >40 TW/cm2 (>4 × 1013 W/cm2) makes them dissociate to yield CF3H and CF4, respectively. The key mechanism of the dissociation of these molecules is field ionization and fragmentation. The excitation
of the stretching vibrations of the C=O bond in the (CF3)2C=C=O and C4F9COI molecules by 4.5-to 5.8-μm femtosecond pulses produced no detectable dissociation up to a fluence of ∼0.5 J/cm2 (or a intensity of ∼2.5 TW/cm2). Probable explanations of this observation are discussed.
Original Russian Text ? V.M. Apatin, V.O. Kompanets, V.B. Laptev, Yu.A. Matveets, E.A. Ryabov, S.V. Chekalin, V.S. Letokhov,
2007, published in Khimicheskaya Fizika, 2007, Vol. 26, No. 4, pp. 18–25. 相似文献
10.
A method is suggested for generating high-intensity secondary pulsed molecular beams in which the kinetic energy of molecules can be controlled by an intense laser IR radiation through the vibrational excitation of molecules in the source. High-intensity [≥1020 molecule/(sr s)] SF6 molecular beams with a kinetic energy of ?1.0 eV without carrier gas and of ?1.9 and ?2.4 eV with carrier He (SF6/He=1/10) and H2 (SF6/H2=1/10) gases, respectively, were obtained. 相似文献