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951.
利用超算符方法求解幅值损耗腔中两个∧型三能级原子与相干光场相互作用系统的主方程,并利用量子条件熵研究了两个初始为|Ψa(0)>和|Φa(0)>纠缠态的原子与光场作用过程中原子的纠缠演化特性.讨论了不同初始原子纠缠度,不同耗散系数以及不同平均光子数对两原子纠缠度的影响.结果表明:①当原子初始处于|Ψa(0)>类纠缠态时,其纠缠度随光场强度以及腔场衰减系数演化.当腔不存在耗散时,纠缠度呈周期性振荡;当腔存在耗散时,纠缠度呈衰减振荡并趋于稳定值;且光强越弱,其稳定值越大;衰减系数越大纠缠达到稳定值所需时间越短.②原子初始处于|Φa(0)>类纠缠态时,其纠缠度只与原子初始纠缠度有关,不随其他因素变化. 相似文献
952.
The appearance of the time derivative of the acceleration in the equation of motion (EOM) of an electric charge is studied. It is shown that when an electric charge is accelerated, a stress force exists in the curved electric field of the accelerated charge, and in the case of a constant linear acceleration, this force is proportional to the acceleration. This stress force acts as a reaction force which is responsible for the creation of the radiation (instead of the radiation reaction force that actually does not exist at low velocities). Thus the initial acceleration should be supplied as an initial condition for the solution of the EOM of an electric charge. 相似文献
953.
Optical feedback characteristics in a helium neon laser with a birefringent internal cavity 下载免费PDF全文
The output characteristics of optical feedback in a helium neon laser with a birefringent internal cavity are studied systematically in five different regions of the gain curve for the two orthogonally polarized modes. When the laser operates in the two end regions of the laser gain curve, one of the two orthogonally polarized modes will be a leading one in optical feedback. Strong mode competition can be observed. However, when the laser operates in the middle region of the laser gain curve, the two modes can oscillate equally with optical feedback. Besides the intensity of the two polarized lights, the total light intensity is also studied at the same time. M-shaped optical feedback curves are found. Particularly, when the average intensities of the two lights are comparable, the intensity modulation curve of the total light is doubled, which can be used to improve the resolution of an optical feedback system.[第一段] 相似文献
954.
955.
A scheme is presented for generating entangled states of multiple
atoms in a cavity. In the scheme the atoms simultaneously interact
with a cavity mode, with the first atom driven by two classical
fields and the other atoms driven by a classical field. Our scheme
is valid even if the cavity decay rate is larger than the effective
coupling strength, which is important for experiment. The generation
of entangled states is conditional on the detection of a photon
decaying from the cavity and thus the fidelity of the entangled
state is insensitive to the detection inefficiency. Furthermore, the
scheme can be applied to the case with any number of atoms in
principle. 相似文献
956.
957.
Xiang-wen Chen Hui-zhen Li Gui-qing Li Ling Qin Zhi-fang Zhang 《International Journal of Infrared and Millimeter Waves》1994,15(9):1555-1566
This paper presents a theoretical method for design quasi-optics power combiner of solid-state millimeter — wave sources, and gives theory analysis to some problem concerned. Here is the structure:
相似文献
1. | Epitome of microwave power combiner. |
2. | Gauss light beam and the field distribution in the resonator. |
3. | The design of the resonator |
(1) | Confocal resonator |
(2) | Objective function |
(3) | The global optimization method and the program flow chart. |
4. | Example |
5. | Reference |
958.
We present a physical scheme to teleport an unknown atomic entangled state via cavity decay. In the teleportation process, four-particle Greenberger-Horne-Zeilinger (GHZ) state is used as quantum channel, and two unknown entangled atoms and two of four atoms in the four-particle GHZ state are trapped in four leaky cavities,respectively. Based on the joint detection of the photons leak out from the four cavities, we can teleport an unknown entangled state to two other remote atoms with certain probability and high fidelity. 相似文献
959.
Transmission spectra of coupled cavity structures (CCSs) in two-dimensional (2D) photonic crystals (PCs) are investigated using a coupled mode theory, and an optical filter based on CCS is proposed. The performance of the filter is investigated using finite-difference time-domain (FDTD) method, and the results show that within a very short coupling distance of about 3λ, where λ is the wavelength of signal in vacuum, the incident signals with different frequencies are separated into different channels with a contrast ratio of 20 dB. The advantages of this kind of filter are small size and easily tunable operation frequencies. 相似文献
960.
研究表明, 峰值强度为1022–1025 W/cm2量级的圆偏振激光脉冲的有质动力场可以直接加速并产生GeV–TeV的单能电子束, 其中被加速电子的能量与激光脉冲的峰值强度成线性定标关系. 为了获得更高能量的电子束, 通过对一维解析模型的分析得到: 如果电子束在激光传播的方向上具一个初始能量E0, 那么这种线性的定标关系可以被打破, 被加速电子束最终的能量可以被放大E0倍. 这是由于具有一定初始能量的电子束不容易被激光脉冲抛在后面, 进而获得更高的加速距离. 二维粒子模拟结果显示: 当电子束的初始能量E0为MeV量级时这个方法是有效的, 而当E0过大时这个方法失效. 这是因为当电子的加速距离远大于激光脉冲的瑞利长度时, 激光强度的衰减使得电子束的加速错过了最佳加速场. 相似文献