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排序方式: 共有1005条查询结果,搜索用时 15 毫秒
101.
Noriaki Nishiguchi Takafumi Kinuta Yoko Nakano Dr. Takunori Harada Dr. Nobuo Tajima Tomohiro Sato Prof. Dr. Michiya Fujiki Prof. Dr. Reiko Kuroda Prof. Dr. Yoshio Matsubara Dr. Yoshitane Imai 《化学:亚洲杂志》2011,6(4):1092-1098
The solid‐state chiral optical properties of a 4‐(2‐arylethynyl)‐benzoic acid/amine supramolecular organic fluorophore can be controlled by changing the arylethynyl group of the achiral 4‐(2‐arylethynyl)‐benzoic acid component molecule rather than the chirality of the amine component molecule. 相似文献
102.
G.-Y. Sun C.-X. Wu Y. Chen Z.-L. Yang 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,49(4):459-464
Using the Keldysh nonequilibrium Green function method, we
theoretically investigate the electron transport properties of a
quantum dot coupled to two ferromagnetic electrodes, with
inelastic electron-phonon interaction and spin flip scattering
present in the quantum dot. It is found that the electron-phonon
interaction reduces the current, induces new satellite polaronic
peaks in the differential conductance spectrum, and at the same
time leads to oscillatory tunneling magnetoresistance effect. Spin
flip scattering suppresses the zero-bias conductance peak and
splits it into two, with different behaviors for parallel and
anti-parallel magnetic configuration of the two electrodes.
Consequently, a negative tunneling magnetoresistance effect may
occur in the resonant tunneling region, with increasing spin flip
scattering rate. 相似文献
103.
超细0.4nm直径单壁碳管的光学特性 总被引:1,自引:1,他引:0
由于纳米碳管的优异机械特性及其丰富多采的光学和电学特性,它自1991年被发现以来一直受到科学家的青睐,纳米碳管研究已成为当今世界上发展最迅速,竞争最激烈的科学前沿领域之一。怎样才能把纳米碳管做得更细小,尺寸更均匀以及如何使众多的纳米碳管排列规整,一直是纳米碳管研究中的难题。我们利用多孔的沸石晶体作为载体,首次成功地研制出了尺寸均一,排列规整的超细单壁纳米碳管,这些超细纳米碳管具有独特的性能,低温下(<20K)甚至呈现出前所未有的一维超导现象。详细介绍了这些超细单壁纳米碳管的制备过程,并着重介绍其在可见光区的光吸收,光发射以及二次谱波的倍频特性。 相似文献
104.
V. R. Khalilov 《Theoretical and Mathematical Physics》2006,149(3):1726-1740
We obtain exact solutions of the Dirac equation in 2+1 dimensions and the electron energy spectrum in the superposition of
the Aharonov-Bohm and Coulomb potentials, which are used to study the Aharonov-Bohm effect for states with continuous and
discrete energy spectra. We represent the total scattering amplitude as the sum of amplitudes of scattering by the Aharonov-Bohm
and Coulomb potentials. We show that the gauge-invariant phase of the wave function or the energy of the electron bound state
can be observed. We obtain a formula for the scattering cross section of spin-polarized electrons scattered by the Aharonov-Bohm
potential. We discuss the problem of the appearance of a bound state if the interaction between the electron spin and the
magnetic field is taken into account in the form of the two-dimensional Dirac delta function.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 149, No. 3, pp. 502–517, December, 2006.
An erratum to this article is available at . 相似文献
105.
基于4400系统,通过引入光电二极管列阵作为传感器,构造了具有光学多道分析功能的信号处理系统。利用该系统对实际的激光空间分布进行了描绘,给出了高斯场分布的相应参数。通过进一步观测p偏振光在K9玻璃上下表面反射光强比(γ)的角度调制曲线,获得了玻璃表面层的光学参数。实验结果表明,该系统测量精度高,可应用在激光时间信号及空间场分布的表征与测量领域。 相似文献
106.
The polarization properties of Gaussian Schell-model (GSM) beams and partially polarized Gaussian Schell-model (PGSM) beams passing through a polarization grating (PG) are studied based on the beam coherence-polarization (BCP) matrix formulism, where the finite size of the PG is considered. Detailed numerical calculation results are given and compared with the previous work. 相似文献
107.
A.E. Barzakh I.Y. Chubukov D.V. Fedorov F.V. Moroz V.N. Panteleev M.D. Seliverstov Y.M. Volkov 《The European Physical Journal A - Hadrons and Nuclei》1998,1(1):3-5
The change in the mean square charge radius and electromagnetic moments of the neutron deficient 155Yb isotope have been determined using resonance ionization spectroscopy in a laser ion source. The data point to an absence
of a marked deformation change for Yb isotopes with N=84−86.
Received: 2 October 1997 / Revised version: 24 October 1997 相似文献
108.
A detailed study of the focal shift of partially polarized Gaussian Schell-model (PGSM) beams is made on the basis of the beam coherence-polarization (BCP) matrix approach. It is shown that, apart from the Fresnel number and truncation parameter, the focal shift of PGSM beams depends on the angle of polarizer and the ratio of degree of spatial coherence. 相似文献
109.
激光偏振参量对光场感生电离电子碰撞机制等离子体电离参量的影响 总被引:2,自引:0,他引:2
以基于光场感生电离电子碰撞机制的类钯氙系统为例,计算并讨论了不同抽运激光偏振对等离子体的电离速率、阈值激光强度、电子在激光场中的剩余能量、各电荷态相对集居数、初始电子能量分布等电离参量的影响,计算结果表明,在相同的激光功率密度下,激光偏振对类钯氙41.8nm4d^95d^1S0-4d^95p^1P1跃迁的X射线激光放大影响很大,圆偏振激光抽运更有利于类钯氙41.8nm4d^95d^1S0-4d^95p^1P1跃迁的X射线激光放大的实现。 相似文献
110.
In terms of the so-called irradiance moments of a light field, the beam quality change, ΔQ, of radially and azimuthally polarized beams caused by propagation through a quartic phase plate (as occurs, for example, in strongly pumped laser rods used in high-power solid-state lasers) is studied. Analytical expressions for ΔQ are given, and a comparison between the scalar and vectorial regimes is also shown. The results are applied to several cases of interest. 相似文献