共查询到20条相似文献,搜索用时 78 毫秒
1.
2.
3.
4.
5.
6.
7.
正交双缝干涉与衍射图象及其规律列光华(广东湛江师院物理系524048)1.引言著名的杨氏双缝干涉实验首次使波动光学建立在实验基础上.本文研究了正交双缝的干涉与衍射综合效应图象及其规律.2.正交双缝夫琅和费衍射规律如图1所示,设正交双缝衍射屏具有二维的... 相似文献
8.
应用计算机数值求解实现激光衍射法精确测缝宽 总被引:3,自引:0,他引:3
在激光夫琅和费衍射法测缝宽实验中,可以发现测算值偏小,缝越宽,偏小程度越大。其原因就在于把平面波单缝衍射的简单缝宽计算公式应用于激光高斯束衍射问题,缝越宽,这种理论模型与实际差别就越大。能否获得激光束衍射条件下缝宽的精确解呢?显然,激光高斯束的复杂性使我们无法像平面波单缝衍射那样推出一个简单、精确的缝宽计算公式。本文尝试利用计机数值求解方法编制出了激光单缝衍射情形下精确的计算机缝宽解算程序,解算结果令人满意。下图是激光衍射测缝宽实验示意图。缝宽为b,缝与观察屏的间距为D,激光器仅 相似文献
9.
不等缝宽多缝的夫琅禾费衍射及计算机模拟 总被引:1,自引:0,他引:1
基于复数法、积分法和矢量法研究不等间距多缝的夫琅禾费衍射的振幅和光强分布.应用Matlab软件进行数值模拟得到衍射图样,分析衍射图样.衍射振幅的推导方法和计算机模拟方法对于研究干涉、衍射等有一定的实际意义和指导意义. 相似文献
10.
多缝夫琅禾费衍射缺级现象分析研究 总被引:1,自引:0,他引:1
本文讨论了多缝夫琅禾费衍射的光强分布特点,编写Matlab程序绘制光强分布曲线,分析了多缝夫琅禾费衍射缺级现象的影响因素,与单缝衍射因子和缝间干涉因子有关. 相似文献
11.
12.
用分子自组装技术制备出纳米金单电子器件,并测量了其伏安特性,根据单电子系统的半经典理论,用MonteCarlo法对其结果进行了模拟.结果表明,模拟出的伏安曲线与实测的伏安曲线有较好的一致性,反映了模拟方法用于单电子器件研究的合理性,此外发现,虽然单电子器件两电极间含有众多的纳米粒子,但在低压区,其伏安特性只与少数纳米粒子有关
关键词:
单电子器件
MonteCarlo模拟
分子自组装 相似文献
13.
Ionization and single electron capture in collision of highly charged Ar16+ ions with helium 下载免费PDF全文
This paper uses the two-centre atomic orbital close-coupling method to study the ionization and the single electron capture in collision of highly charged Ar^16+ ions with He atoms in the velocity range of 1.2-1.9 a.u.. The relative importance of single ionization (SI) to single capture (SC) is explored. The comparison between the calculation and experimental data shows that the SI/SC cross section ratios from this work are in good agreement with experimental data. The total single electron ionization cross sections and the total single electron capture cross sections are also given for this collision. The investigation of the partial electron capture cross section shows a general tendency of capture to larger n and l with increasing velocity from 1.2 to 1.9 a.u.. 相似文献
14.
Rabi nutations and Hahn echo modulation of a single electron spin in a single defect center have been observed. The coherent evolution of the spin quantum state is followed via optical detection of the spin state. Coherence times up to several microseconds at room temperature have been measured. Optical excitation of the spin states leads to decoherence. Quantum beats between electron spin transitions in a single spin Hahn echo experiment are observed. A closer analysis reveals that beats also result from the hyperfine coupling of the electron spin to a single 14N nuclear spin. The results are analyzed in terms of a density matrix approach of an electron spin interacting with two oscillating fields. 相似文献
15.
We study the coupling of a single nitrogen-vacancy center in diamond to a nearby single nitrogen defect at room temperature. The magnetic dipolar coupling leads to a splitting in the electron spin resonance frequency of the nitrogen-vacancy center, allowing readout of the state of a single nitrogen electron spin. At magnetic fields where the spin splitting of the two centers is the same, we observe a strong polarization of the nitrogen electron spin. The amount of polarization can be controlled by the optical excitation power. We combine the polarization and the readout in time-resolved pump-probe measurements to determine the spin relaxation time of a single nitrogen electron spin. Finally, we discuss indications for hyperfine-induced polarization of the nitrogen nuclear spin. 相似文献
16.
Charge‐transfer complex formations of tetracyanoquinone (cyanil) and aromatic electron donors 下载免费PDF全文
Single‐electron oxidants are the primary reagents for investigations of the new oxidants and the development of electron‐accepting materials for application in optoelectronics. Quinones are the well‐known class of the neutral single‐electron oxidants. Here, we present the properties of the strongest neutral electron acceptor of this class tetracyanoquinone (cyanil) and investigate its electron‐accepting strength by analyzing the charge‐transfer complex formations with the aromatic donor molecules. Charge‐transfer complexes of tetracyanoquinone with aromatic electron donors are characterized spectroscopically in solution and isolated as the single crystals. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
17.
A unit event of electron-electron scattering in LiF layers is studied by correlation spectroscopy of scattered electrons. The energy distribution of electrons in a correlated pair when a 15-to 55-eV free electron is scattered by a valence electron of LiF is studied. It is shown that single electron-electron scattering prevails and the distribution is uniform when the energy of the primary electron is below 25 eV. As the energy of the primary electron increases, the formation of correlated pairs of electrons with equal energies becomes the most probable. With the energy of the primary electron above 40 eV, the pairs with substantially different electron energies dominate. Such evolution of the energy distribution of the electrons in the pair stems from the fact that first one and then the other electron of the pair successively takes part in electron-electron scattering. A phenomenological model for the single scattering and double scattering of primary electrons in LiF films is considered. Results obtained indicate that the strengths of single scattering and double scattering channels become comparable at electron energies above 25 eV. 相似文献
18.
This paper reviews the theory and practice of Lorentz electron microscopy in the investigations of magnetic domain structure. The transmission electron microscope, the necessary operational procedures and imaging theory required for Lorentz microscopy are described. Magnetization devices and other facilities that have been developed over the last two years to study domain magnetization in situ in the electron microscope are discussed. Results so far obtained on such materials as thin single crystals and polycrystals of ferromagnetic metals, magnetic oxides, evaporated and electrodeposited single crystal and polycrystal films, and whisker and single domain particles are reviewed. The methods available for preparing specimens in a suitable form for transmission electron microscopy are described. 相似文献
19.
Highly oriented and vertically aligned single crystalline ZnO nanotubes were fabricated on Al2O3 (0001) substrates by plasma-molecular beam epitaxy without employing any external metal catalysts or templates. Field emission scanning electron microscope images indicate that the regularly aligned ZnO nanotubes with uniform size distribution were obtained. The chimney-like single crystal ZnO nanotube was confirmed by the transmission electron microscope and selected area electron diffraction pattern of the single nanotube. The formation mechanism of the nanotubes was also described briefly. 相似文献
20.
Multiple ionization of argon accompanied by electron loss and capture of 0.22-6.35 MeV C^q+ ions 下载免费PDF全文
In this paper a projectile ions recoil ions coincidence technique is employed to investigate the target ionization and projectile charge state changing processes in the collision of 0.22-6.35 MeV Cq^+ (q = 1 - 4) ions with argon atoms. The partial cross section ratios of the double, triple, quadruplicate ionization to the single ionization (or the single capture) of argon associated with single electron loss (or single electron capture) by the projectile are measured and compared with the previous experimental results. In the present experiment, it is observed that the ratios of ionization cross sections R associated with single loss and single capture depend strongly on the projectile charge state and vary significantly with different reaction channels as impact energy increases. In addition, this paper gets empirical scaling laws for the ionization cross section ratios R corresponding to the projectile single loss and finds that the ratios of the double ionization to the single ionization associated with single electron capture remain constant in the present energy range. 相似文献