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71.
Wang Chang-biao Tu Jian-nan Jian Hua-bei Sun Yan 《International Journal of Infrared and Millimeter Waves》1986,7(7):1005-1035
The kinetic theory based on the expansion of local field in the guiding center coordinate system, presented by paper[1]–[3], has successfully developed into a theoretical system. The mathematical background and physical explanation of setting up the guiding center coordinate system is expounded in the paper. By using the methods of the guiding center and waveguide coordinate systems respectively, the same dispersion equations for interaction of an axially symmetrical single momentum electron beam with TEmn field in the circular waveguide are rigorously derived. A number of mistakes in paper[4] are indicated as well. 相似文献
72.
Continuing Chicone and Jacobs’ work for planar Hamiltonian systems of Newton’s type, in this paper we study the local bifurcation of critical periods near a nondegenerate center of the cubic Liénard equation with cubic damping and prove that at most 2 local critical periods can be produced from either a weak center of finite order or the linear isochronous center and that at most 1 local critical period can be produced from nonlinear isochronous centers. 相似文献
73.
Yuan Zhou Dong-Yan Lü Guang-Hui Wang Yan-Hua Fu Ming-Yao He Hong-Tao Ren 《理论物理通讯》2021,73(6):65101
It remains a great challenge to realize direct manipulation of a nitrogen-vacancy(NV) spin at the single-quantum level with a microwave(MW) cavity. As an alternative, a hybrid system with the spin–phonon–photon triple interactions mediated by a squeezed cantilever-type harmonic resonator is proposed. According to the general mechanical parametric amplification of this in-between phonon mode, the direct spin–phonon and photon–phonon couplings are both exponentially enhanced, which can even further improve the coherent manipulation of a single NV spin and MW photon with a higher efficiency. In view of this triple system with enhanced couplings and the additional sideband adjustable designs, this scheme may provide a more efficient phonon-mediated platform to bridge or manipulate the MW quantum and a single electron spin coherently. It is also hoped to evoke wider applications in the areas of quantum state transfer and preparation,ultrasensitive detection and quantum nondestructive measurement, etc. 相似文献
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75.
YUAN DaoYi ZHANG YongQiang TU YongQiang CHEN ZhiHua & ZHAO Xiong State Key Laboratory of Applied Organic Chemistry 《中国科学:化学》2010,(1)
Construction of the polyaryl quaternary unit through a ZnBr2 catalyzed tandem coupling/semipinacol rearrangement participated by allylic cations was reported for the first time. 相似文献
76.
78.
This paper investigates the short-living absorption and the emission of CsI(Na) under a pulsed electron beam (Еe=0.25 MeV, t1/2=15 ns and W=0.003…0.16 J/cm2). The bands of singlet self-trapped excitons, as well as Na0 and Vk color centers have been detected in the transient absorption spectrum of CsI(Na). It has been found that the activator luminescence spectrum, peaking at 3.0 eV, fits a Gaussian (Em=3.0 eV and FWHM=0.44±0.02 eV at 80 K) and remains the same at different time delays within 10−8-10−3 s. The decay kinetics of the 3.0 eV emission has one nanosecond exponential component and two microsecond ones with time constants 1.0 and 3.0 μs, which remain unchanged within 78-150 K. It is concluded that the activator emission is due to the radiative annihilation of sodium-perturbed two halide excitons from the non-relaxed singlet state. The pathways of such excitons creation are discussed. 相似文献
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80.