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971.
Entanglement swapping without joint measurement via a Λ-type atom interacting with bimodal cavity field 下载免费PDF全文
This paper proposes a scheme for realizing entanglement swapping in cavity QED. The scheme is based on the resonant interaction of a two-mode cavity field with a ∧-type three-level atom. In contrast with the previously proposed schemes, the present scheme is ascendant, since the fidelity is 1.0 and the joint measurement isn't needed. And the scheme is experimentally feasible based on the current cavity QED technique. 相似文献
972.
Remote preparation of a Greenberger--Horne--Zeilinger state via a two-particle entangled state 总被引:2,自引:0,他引:2 下载免费PDF全文
We present two schemes for realizing the remote preparation of a
Greenberger--Horne--Zeilinger (GHZ) state. The first scheme is to remotely
prepare a general N-particle GHZ state with two steps. One is to prepare a qubit
state by using finite classical bits from sender to receiver via a
two-particle entangled state, and the other is that the receiver introduces
N - 1 additional particles and performs N - 1 controlled-not (C-Not)
operations. The second scheme is to remotely prepare an N-atom
GHZ state via
a two-atom entangled state in cavity quantum electrodynamics (QED). The two
schemes require only a two-particle entangled state used as a quantum
channel, so we reduce the requirement for entanglement. 相似文献
973.
CH(cross-bar H-type structure)结构是近几年提出的一种适用于低β的新型DTL(drift tube linac)加速结构,同IH(interdigital H-type structure)结构相比,CH结构可以工作在更高的频率(150~700 MHz)下,从而可以得到更高的输出能量(150 MeV)。由于DTL腔体为准周期结构,通过对单元腔的MWS(microwave studio)模拟及优化,得到了工作频率为350 MHz,单核能从6 MeV到66 MeV时的腔体并联阻抗及其它腔体参数,并对腔体单元数对腔体特性参数及谐振频率的影响做了定性分析。分析表明:对于CH结构,其有效并联阻抗远大于传统的DTL结构,对于350 MHz的工作频率,在6 MeV时将近100 MΩ/m,即使在能量高达66 MeV时,其有效并联阻抗也大于40 MΩ/m;单元腔近似是一种非常有效的分析DTL加速结构的方法,单元腔计算结果和整腔计算结果相比,谐振频率的相对偏差小于1%; 对于有效并联阻抗的计算,误差也在10%之内。 相似文献
974.
CAO Zhuo-Liang LI Da-Chuang 《理论物理通讯》2008,49(2):369-372
An experimentally feasible scheme for teleportation of an unknown two-atom entangled state is proposed. Our scheme uses a duster state as the quantum channel, where we do not need any joint Bell-state measurement. Moreover the successful probability and fidelity of teleportation can both reach 1.0. The current scheme can be realized within the current experimental technology. 相似文献
975.
利用模式展开和场匹配理论,建立了具有突变结构谐振腔的散射矩阵。在此基础上编制了FORTRAN计算程序,并对Ka波段TE01模回旋速调管的具有突变结构的开放式输出腔进行了数值计算。分析了回旋速调管输出腔的腔体长度和半径变化,以及输出耦合孔的半径和厚度变化对输出腔的品质因数和频率的影响。结果表明:由程序模拟输出腔所得到的计算结果与HFSS软件的结果一致;与冷测实验结果相比,品质因数的相对偏差为1.65%,谐振频率的偏差为10 MHz。 相似文献
976.
Seung Pil Yoo 《Applied Acoustics》2008,69(3):215-224
A flow over an open cavity causes a cavity resonance, which is a feedback mechanism between the acoustic waves and the pressure fluctuation of the cavity flow. Previous research on the reduction of the cavity resonance has focused on suppressing the flow disturbance. This paper presents a time-delayed phase-control method to reduce the global noise of the cavity. Acoustic feedback of the cavity noise, which amplifies the flow disturbance, can be generally reduced by this control method, regardless of the flow physics. The positions of the sensors and the actuator are determined to increase the control efficiency. Experiments show that this control method reduces the peak of the flow oscillation by suppressing the acoustic feedback. 相似文献
977.
Higher harmonic cavity used in the third generation synchrotron light source increases the Touschek lifetime.The higher harmonic cavity of Shanghai Synchrotron Radiation Facility(SSRF)is a 1.5 GHz passive superconducting cavity.Its higher order modes(HOM)are extracted by a ferrite HOM damper out of the cryostat.Multi-cell cavity is chosen concerning the voltage.The harmonic cavity dynamics,beam dynamics with passive harmonic cavity and the design of single cell cavity are included in this paper. 相似文献
978.
RF cold test of a novel C-band cavity beam position monitor (PBM) to be used in the SDUVFEL Test Facility is described.The test results are presented and some characteristics discussed.The main parameters obtained are in reasonable agreement with the analytical estimations.Effective suppression of the common mode has been demonstrated.The position sensitivity over the test region of±0.5 mm is about -21.58 dB/10 μm for the TM110 mode and is linear in the central region of the BPM cavity. 相似文献
979.
980.
A cavity quantum electrodynamics scheme for preparing a genuinely entangled state [A. Borras, et al., J. Phys. A 40 (2007) 13407] on six two-level atoms is proposed. In the scheme, the atom-cavity detuning is much bigger than the atom-cavity coupling strength and the necessary preparation time is much shorter than the Rydberg-atom lifespan. Hence the scheme has two distinct features, i.e., insensitive to the cavity decay and the atom radiation. 相似文献