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991.
Optical four-wave mixing due to the resonant spin nonlinearity in n-InSb was observed in magnetic fields up to 1.4 T. The mixing of two CO-laser frequencies ω1 and ω2 = ω1 - Δω yields radiation with frequencies ω1 + 2Δω, ω1 + Δω, ω1 - 2Δω, and ω1 - 3Δω. We found the resonant contribution to the third order nonlinear susceptibility arising from the spin-flip interaction to increase by more than two orders of magnitude when ω1 is varied from 1760 cm-1 to 1896 cm-1. With the lasers working simultaneously Q-switched we observed radiation at ω1 + Δω and ω1 - 2Δω due to the mixing caused by the nonparabolicity of the conduction electrons even without an external magnetic field. At the resonant magnetic field the intensity of the mixed radiation is increased by more than one order of magnitude and is also observed when the laser pulses do not hit the sample simultaneously as long as the time difference between the two pulses does not exceed 450 ns. This points to a spin dephasing time T2 of about 100 ns. 相似文献
992.
S. Nagamiya L. Anderson W. Brückner O. Chamberlain M.-C. Lemaire S. Schnetzer G. Shapiro H. Steiner I. Tanihata 《Physics letters. [Part B]》1979,81(2):147-150
Inclusive proton spectra, as well as two-particle correlations, resulting from collisions between energetic nuclei have been measured. Protons associated with large momentum transfers show exponential-type energy distributions having a decay constant about (70–90 MeV)?1. For light-mass targets a strong two-particle correlation has been observed, which is kinematically consistent with quasi-elastic pp scatterings. 相似文献
993.
H. Weber K. Braun E. Unsin H. Widey G. Zäpfel Peter F. Heil W. Krämer K. -W. Schulte Th. Fischer G. Fandel 《Mathematical Methods of Operations Research》1980,24(6):B199-B206
Ohne Zusammenfassung 相似文献
994.
Alkali metal solutions in hexamethylphosphotriamide effect the cleavage of various sulfonamides and sulfonates under mild conditions.Sulfonamides give amines in good yields: the presence of a protic cosolvent is not necessary. Sulfonates of all types (e.g. tosylate, benzylate, mesylate) give the alcohol always contaminated with a little of the corresponding hydrocarbon. 相似文献
995.
996.
Tables are given to enable effective algorithms to be formed for computer calculation of the overlap and Coulomb integrals with Slater-type orbitals in complexes with rare-earth or transition-metal central ions. 相似文献
997.
998.
B. Anders U. Berghaus H. Brückmann P. Lara C. Pegel H. Salehi A. Schütte K. Sinram K. Wick 《Physics letters. [Part B]》1979,87(4):346-348
At the Hamburger Isochronous Cyclotron the formation of the particle unstable ground state of has been investigated in the reaction α + d → α + p + n at Eα = 28.3 MeV. The neutrons were detected in two liquid scintillation counters, while a large Si (Li) detector was used to observe the α-particles. In a first analysis, the tensor polarization parameters of the five-nucleon system 5Li are determined from the experimental data. The results are in quite good agreement with theoretical predictions of Hackenbroich et al. 相似文献
999.
P. Bräunlich K. Reiber A. Scharmann 《Zeitschrift für Physik A Hadrons and Nuclei》1965,183(5):431-446
Luminescence decay times of CaWO4 single crystals after excitation with UV-light and electrons and thermoluminescence after irradiation with X-rays and electrons have been investigated. Under certain conditions thermally stimulated and photoconductivity is observed. The experimental results lead to a modification of the usual model of the luminescence centre in CaWO4. 相似文献
1000.
J. Jänecke 《Zeitschrift für Physik A Hadrons and Nuclei》1965,183(5):499-503
If aβ-decaying H4 exists a super-allowed transition to the excited analogue state of He4 is possible. Such a decay mode was not considered in previous experiments. The reaction Li6 (γ, 2p) H4 was used to produce H4. No super-allowedβ ?-decay of H4 could be observed and upper limits for the production cross section are given. 相似文献