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原子束在慢波场中的多普勒频移的观察 总被引:1,自引:0,他引:1
报道了在慢波场中原子波谱多普勒频移随微波慢波系数的变化,并讨论产生这种现象的原因,实验中观察到慢波场中的原子多普勒频移现象,给出了钠原子在慢小系数分别为5.20和10.67情况下的微波波谱,证实了原子微波慢波波谱中多普勒频移正比于慢波系数。 相似文献
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本文对铯原子频标中的Majorana跃迁频移进行理论上的探讨。通过经受低频和微波多重共振的多能级系统的铯原子量子态变化的分析,认为产生这种频移的物理机制在于Cs133原子穿过空间变化磁场时感应了塞曼子能级间的跃迁,扰动了频标赖以工作的两个能级相应态的相位,这个过程又相干于Ramsey共振过程中,最后导致Ramsey共振频移。基于此机制,解释一些有关实验现象并提出消除和减少Majorana跃迁的判断方法。 相似文献
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基于微波电光调制的布里渊光时域分析传感器 总被引:12,自引:4,他引:8
针对布里渊光时域分析分布式传感原理和受激布里渊散射的特点,应用微波电光调制分布反馈式半导体激光器产生频移可调的探测光,和传感光纤中相反方向传输的脉冲激励光进行受激布里渊散射作用,当探测光和激励光的频率差在布里渊频移附近时,频移探测光和激励光产生受激布里渊散射,通过改变探测光的频移值,检测探测光功率信号,可得到沿光纤各处的布里渊频移,再利用布里渊频移和应变(或温度)的关系,计算得到沿光纤分布的传感量。设计了基于微波电光调制的布里渊光时域分析传感器实验系统,实现了25km的分布式温度传感,达到5m的空间分辨力和3℃的温度分辨力。 相似文献
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本文建议了一个测量位相共轭镜耦合到染料激光器后,当波长自扫描时,BaTiO_3晶体内的运动光栅的多普勒频移的方法,实验结果表明,多普勒频移Δf<0.2Hz.进一步的分析显示,多普勒频移不能解释朝长波方向扫描的波长自扫描现象. 相似文献
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实验中观察到由于激发波长不同,吸附于银溶胶上的哟啶分子及其衍生物的不同频移的拉曼带增强比出现明显的差异,骈对此现象给予理论解释。 相似文献
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实验中观察到由于激发波长不同,吸附于银溶胶上的吡啶分子及其衍生物的不同频移的拉曼带增强比出现明显的差异,并对此现象给予理论解释。 相似文献
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We have proved experimentally that the frequency shift formula of AC Zeeman effect presented by us is correct. In a 87Rb atomic frequency standard we add a new microwave field which causes the frequency shift of O-O transition frequency of 87Rb atomic ground state. This frequency shift as a function of frequency and power of the added microwave field is measured. The experimental results agree with theory. 相似文献
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We have proved experimentally that the frequency shift formula of AC Zeeman effect presented by us is correct. In a 87Rb atomic frequency standard we add a new microwave field which causes the frequency shift of O-O transition frequency of 87Rb atomic ground state. This frequency shift as a function of frequency and power of the added microwave field is measured. The experimental results agree with theory. 相似文献
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K. F. Renk A. Rogl B. I. Stahl A. Meier Yu. I. Koschurinov D. G. Pavelev V. Ustinov A. Zhukov N. Maleev A. Vasilyev 《International Journal of Infrared and Millimeter Waves》2006,27(3):373-380
We report on a GaAs/AlAs superlattice frequency mixer for detection of submillimeter waves. The mixer is based on the nonlinear
miniband transport giving rise to domains excited under the action of a microwave field. We designed the mixer for broadband
operation (300–600 GHz). For studying basic properties, we investigated the mixer as a harmonic mixer in 15th order to detect radiation at a radio frequency (RF) near 300 GHz using local oscillator (LO) radiation of a frequency near
20 GHz. We reached a noise equivalent power (NEP) of about 10 fW/Hz. We also show that the use of the superlattice mixer together
with a superlattice frequency multiplier allows to realize a superlattice-based free-space transmission line for submillimeter
waves. 相似文献
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The mechanism of the development of the effect of microwave pulse shortening in a plasma relativistic microwave generator with a power of 108 W is determined using numerical simulation. Methods for eliminating the causes of microwave generation quenching are proposed. It is shown that the emission time can be significantly increased. 相似文献
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为了准确诊断真空中微波等离子体喷流的电子数密度,利用统一的发射和单郎缪尔探针测量等离子体的空间电位,再测量等离子体的电流-电压特性曲线.根据空间电位测量结果,在等离子体的电流-电压特性曲线上能准确地获取饱和电流,从而处理出电子数密度.最后的诊断实验表明,当真空环境压强为2—6 Pa、等离子体发生器以60 W以下的微波功率击穿流量范围是42—106 mg/s的氩气时,所产生的微波等离子体喷流中电子数密度分布在1×1016—7.2×1016/m3范围内. 相似文献
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Katsunari Enomoto Pavle Djuricanin Ilja Gerhardt Omid Nourbakhsh Yoshiki Moriwaki Walter Hardy Takamasa Momose 《Applied physics. B, Lasers and optics》2012,109(1):149-157
We propose the use of superconducting microwave cavities for the focusing and deceleration of cold polar molecular beams. A superconducting cavity with a high quality factor produces a large ac Stark shift in polar molecules, which allow us to efficiently control molecular motion. Our discussion is based on the experimental characterization of a prototype cavity: a lead–tin-coated cylindrical copper cavity, which has a quality factor of 106 and tolerates several watts of input power. Such a microwave device provides a powerful way to control molecules not only in low-field-seeking states, but also in high-field-seeking states such as the ground rotational state. 相似文献
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In the present study, resolved OD EPR spectra were measured for the 431, 423, and 413 levels of the Ã1 Au 00 vibronic state. Values of the fine and hyperfine constants were estimated from an analysis of these spectra for the triplet rotational levels, coupled by the intramolecular interactions with the singlet levels studied. It was shown that the microwave power dependence differs significantly for different lines of the OD EPR spectrum. This difference can be explained by a model where the microwave field saturation effect is observed for different OD EPR lines at different power values of the microwave field. The decay profile can be fitted by a biexponential function in the presence of both magnetic and microwave fields. The observed data were analysed using the electron and nuclear spin decoupling mechanism in the limit of low level density. 相似文献
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Microwave power coupling with electron cyclotron resonance plasma using Langmuir probe 总被引:1,自引:0,他引:1
Electron cyclotron resonance (ECR) plasma was produced at 2.45 GHz using 200–750 W microwave power. The plasma was produced from argon gas at a pressure of 2 × 10???4 mbar. Three water-cooled solenoid coils were used to satisfy the ECR resonant conditions inside the plasma chamber. The basic parameters of plasma, such as electron density, electron temperature, floating potential, and plasma potential, were evaluated using the current–voltage curve using a Langmuir probe. The effect of microwave power coupling to the plasma was studied by varying the microwave power. It was observed that the optimum coupling to the plasma was obtained for ~ 600 W microwave power with an average electron density of ~ 6 × 1011 cm???3 and average electron temperature of ~ 9 eV. 相似文献