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431.
Chang-Yong Chen 《International Journal of Theoretical Physics》2008,47(5):1397-1408
A scheme has been proposed for generating the macroscopic superpositions and the entanglement between the mesoscopic squeezed
vacuum states by considering the two-photon interaction of N two-level atoms in a dissipative cavity with high quality factor assisted by a strong driving field. A number of multiparty
entangled states between the atoms and the squeezed vacuum states, among the atoms, and among the squeezed vacuum states,
can be prepared by virtue of a specific choice of the cavity detuning and the detuning of applied coherent field under the
dissipation condition. The corresponding analytical expressions of the influence can be given. Moreover, we can also give
a series of macroscopic entangled states between the usual coherent states and the squeezed vacuum states using the combination
of the dissipative one-photon interaction Hamiltonian with the dissipative two-photon interaction Hamiltonian. We also discuss
the experimental feasibility. Our scheme can be realized in the current techniques on the cavity QED. 相似文献
432.
The exhaustive line positions analysis of the absorption spectrum of carbon dioxide in natural abundance has been performed on the basis of high sensitivity CW-Cavity Ring Down spectroscopy between 5851 and 7045 cm−1 (1.71-1.42 μm). The achieved sensitivity (noise equivalent absorption αmin ∼ 2-5 × 10−10 cm−1) have allowed the detection of 8293 transitions of the 12C16O2, 16O12C17O and 16O12C18O isotopologues. They belong to a total of 130 bands. Line intensities of the weakest transitions are on the order of 2 × 10−29 cm/molecule. The rovibrational assignments were performed on the basis of accurate predictions of the effective Hamiltonian model of the respective isotopologues. The band-by-band analysis has allowed deriving accurate spectroscopic parameters of 121 bands from a fit of the measured line positions. A number of resonance interactions were identified. In particular, the first observation of an interpolyad coupling is reported for the 16O12C18O isotopologue. The results of the complete line positions analysis are provided as Supplementary material.The obtained experimental dataset which is the most complete in the considered region, has been used for a critical review of the most currently used spectroscopic databases of carbon dioxide: HITRAN, GEISA, HITEMP, and the recent JPL and CDSD databases. 相似文献
433.
用W态实现量子隐形传态的腔QED方案 总被引:1,自引:1,他引:0
本文提出一个用类W态作为纠缠通道,采用不同于文献[19]的测量基来实现量子隐形传态的腔QED方案.在这个方案里,只需要利用原子和腔场通过J-C哈密顿量发生共振相互作用,一步就可制备纠缠通道.另外,通过原子与腔场的失谐作用,利用Bell态测量,可实现概率为100%的量子隐形传态.在目前的腔QED技术条件下,该方案是可以实现的. 相似文献
434.
We propose a new integrated demultiplexer model using the two-dimensional photonic crystal (2D PC) through the hexagonal resonant cavity (HRC) for the International Telecommunication Union (ITU) standard. The integrated model of demultiplexer for both 25 GHz and 50 GHz has been designed for the first time. The demultiplexer consists of bus input waveguide, drop waveguide, Hexagonal Resonant Cavity (HRC), 6 Air Hole Filter (6-AHF), 7 Air Hole Filter (7-AHF). The 7-AHF is used to filter 25GHz wavelength, and the 6-AHF filter is used to filter 50 GHz wavelength. The Q-factor on the designed demultiplexer is flexible based on the idea of increasing the number of air holes between drop waveguide and resonant cavity. The demultiplexer is designed to drop maximum 8 resonant wavelengths. One side of demultiplexer is able to drop 50 GHz ITU standard wavelengths, which are of 1556.3 nm, 1556.7 nm, 1557.1 nm and 1557.5 nm, and further the other facet is able to drop 25 GHz wavelengths, which are of 1551.4 nm, 1551.6 nm, 1551.8 nm, and 1552.0 nm. The proposed demultiplexer may be carried out within the integrated dual system. This system is able to lessen the architecture cost and the size is miniaturized substantially. 相似文献
435.
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437.
目前,国际最高光辐射功率基准为低温辐射计,其可探测光谱范围覆盖真空紫外到太赫兹波段(115 nm~T Hz),利用真空低温超导条件下的电替代测量原理,将光辐射功率参数溯源到可以精确测量的电参数进行高精度测量,实现超宽光谱范围的光辐射绝对功率测量,其测量不确定度达到10-5量级,尤其在国防军事和光辐射计量领域,光电有效载... 相似文献