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951.
952.
Zhi-Cheng Wang Gong Yu Song-Yi Zheng Wen-An Guo 《Zeitschrift für Physik B Condensed Matter》1994,95(1):95-100
We consider an ensemble of three-level configuration atoms in an optical cavity, interacting through two-photon transitions with a cavity mode, driven by a broad-band squeezed input of finite amplitude. The atom-cavity system is coupled to reservoirs to describe the losses of the atoms and the cavity. Optical spectra in the transmitted and the reflected field are calculated and analysed in the good cavity limit, for the purely absorptive resonant case and the general case, respectively. 相似文献
953.
T.Ya. Gorbach G.Yu. Rudko P. S. Smertenko S. V. Svechnikov M.Ya. Valakh 《Applied Physics A: Materials Science & Processing》1994,58(2):183-186
Visible room-temperature luminescence of Anisotropically Chemically Etched (ACE) silicon under spontaneous chemical surface modification in HNO3:HF solution is reported. The material is investigated by SEM, AES, IR transmission and Raman scattering methods. 相似文献
954.
Some representative potentials of the anharmonic-oscillator type are constructed. Some corresponding spectra-shift operators are also constructed. These operators are a natural generalization of Fok creation and annihilation operators. The Schrodinger problem for these potentials leads to an equidistant energy spectrum for all excited states, which are separated from the ground state by an energy gap. The general properties of the dynamic system generated by spectral-shift operators of third degree are analyzed. Several examples of such anharmonic oscillators are discussed. The relationship between the eigenvectors of the Schrodinger problem and a certain type of nonclassical orthogonal polynomials is established. 相似文献
955.
A. A. Klopotov Yu. A. Timoshnikov V. A. Plotnikov N. M. Matveeva Yu. A. Sazanov I. A. Lapsker 《Russian Physics Journal》1994,37(8):746-749
The influence of small doses of radiation on the structure-sensitive properties of CuTi amorphous metallic alloy (AMA) is investigated. The AMA exhibit brittle behavior. It is found that, in samples exposed to radiation, the nonlinear behavior of the load-elongation curve is more pronounced and begins sooner. A small change in the fracture morphology in these samples is observed by raster electron microscopy. The additional broadening of the first amorphous maximum and its shift on the x-ray diffraction patterns correlates with increase in the dose. The modification of the structural-relaxation processes on heating the initial and irradiated samples is traced by the acoustic-emission method. The activation energy of these processes is determined.Tomsk State Architectural and Building Academy. Translated from Izestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 55–59, August, 1994. 相似文献
956.
A compound system made up of two vector particles is described using field operators transformed according to the (1.0)(0.1) representation of a Lorentz group. The interaction of vector particles with an electromagnetic field is also studied.N. G. Chernyshevskii Saratov State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 110–115, September, 1994. 相似文献
957.
958.
S. N. Tskhai Yu. B. Udalov P. J. M. Peters W. J. Witteman V. N. Ochkin 《Applied physics. B, Lasers and optics》1996,62(1):11-14
A radiofrequency excited atomic Xe slab laser with an active volume of 2 × 10 × 300 mm3 using a quartz envelope containing the laser-gas mixture shows a stable cw performance with an output power of almost 1 W. The free-running system oscillates, depending on gas composition and density, on several lines between 1.73 and 3.51 m. Line competition phenomena are observed. Single-line oscillation yields more than 500 mW. 相似文献
959.
960.
We show that theq-Weyl coefficients of the quantum algebraSU
q
(3) are equal to theq-Racah coefficients of the quantum algebraSU
q
(2) (up to a simple phase factor). Using aq-analog of the resummation procedure we obtain also theq-analogues of all known general analytical expressions for the 6j-symbols (or the Racah coefficients) of the quantum algebraSU
q
(2) starting from one such formula.Presented at the 4th Colloquium Quantum groups and integrable systems, Prague, 22–24 June 1995.The research described in this publication was supported in part by Grants No. MB1000 and No. NRC000 from International Science Foundation. 相似文献