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排序方式: 共有969条查询结果,搜索用时 31 毫秒
51.
通过求解系统的Milburn方程,研究了两个二能级原子和单模场相互作用系统中原子间纠缠和贝尔不等式破坏随时间的演化特性,讨论了偶极相互作用、场与原子的失谐量对纠缠度以及贝尔不等式破坏的影响.结果表明:原子间偶极-偶极相互作用对纠缠度和贝尔不等式破坏有显著影响,失谐量增大会使两原子的纠缠度和贝尔不等式破坏变大,并且两原子所能达到稳定的纠缠受偶极相互作用系数与失谐量两者之差的影响.同时还发现两原子的纠缠与贝尔不等式破坏并不是单调的函数关系,很小的纠缠也可以产生贝尔不等式破坏.
关键词:
Milburn理论
偶极-偶极相互作用
失谐量
贝尔不等式破坏 相似文献
52.
Grzegorz Stepniak Lukasz Maksymiuk Jerzy Siuzdak 《Optical and Quantum Electronics》2007,39(15):1281-1288
Frequency response of passive optical network (PON) based on multimode fibers is investigated. The network comprises fibers,
connectors and splitters/couplers. It is shown that due to mode filtering at splitters, the frequency response is different
for different network nodes in otherwise symmetrical network. 相似文献
53.
54.
Phase-matched third-harmonic UV generation using low-order modes in a glass micro-fiber 总被引:1,自引:0,他引:1
Victor Grubsky 《Optics Communications》2007,274(2):447-450
We observe phase-matched third-harmonic generation at 355 nm in a low-order mode of a sub-micron diameter glass fiber. The third-harmonic signal exhibits a sharp resonance for a fiber diameter d = 0.49 ± 0.02 μm, in excellent agreement with the value d = 0.506 μm predicted by theory. The third-harmonic conversion efficiency is 2 × 10−6, and is limited by the pump power (1 kW) and effective fiber length (100 μm). 相似文献
55.
Hyun Keol Kim 《Journal of Quantitative Spectroscopy & Radiative Transfer》2007,104(2):248-256
A conjugate gradient method without line search (CGMWLS) is presented. This method is used to retrieve the local maps of absorption and scattering coefficients inside the tissue-like test medium, with the synthetic data. The forward problem is solved with a discrete-ordinates finite-difference method based on the frequency domain formulation of radiative transfer equation. The inversion results demonstrate that the CGMWLS can retrieve simultaneously the spatial distributions of optical properties inside the medium within a reasonable accuracy, by reducing cross-talk between absorption and scattering coefficients. 相似文献
56.
In this article we propose to partially integrate the antenna positioning (APP) and frequency allocation problems (FAP). The traditional wireless network design process examines these two major issues sequentially in order to avoid the very high complexity associated with the simultaneous resolution of the two problems. The proposed integration involves the introduction of interference protection guarantees within the APP. It is customary to define such guarantees in an intermediate step and to use them as input to FAP, in order to protect against interference in critical areas. The proposed approach consists of selecting these protections while solving the APP, allowing the optimization procedure to exploit the degrees of freedom that this would offer. Results on two real-life problem instances indicate a significant improvement in interference levels and resource utilization. 相似文献
57.
A compact design for a single mode Tm:YAG laser is presented. With two thin infrasil etalons as the only intracavity tuning elements a tuning range from 1940 to 2030 nm with a gap between 2000 and 2020 nm can be realized. The laser emits in two longitudinal modes separated by 1 GHz. Pumped with 500 mW power from a Ti:sapphire laser at 786 nm the output is above 50 mW over the entire tuning range. Frequencies can be rapidly varied over a range of 4 GHz. 相似文献
58.
The exact frequency shift of an AFM non-uniform probe with an elastically restrained root, subjected to van der Waals force, is derived. The original distributed system is considered and then its exact fundamental solutions and the general frequency equation are derived. Results are compared with those by the force gradient method and the perturbation method. The effects of several parameters on the sensitivity of measurement are investigated. Results show that the interpretation of frequency shift by using the force gradient method is unsatisfactory. The smaller the amplitude of oscillation and the tip–surface distance are, the larger the frequency shift. The design of a taper beam is recommended for increasing the sensitivity of measurement. 相似文献
59.
Laser diodes have the features of a single-mode operation and a frequency tunability. Holographic interferometry is described for investigating the vibrating amplitude and phase with a frequency-modulated laser diode. Sinusoidal wavelength change by varying laser injection current produces the sinusoidal phase modulation of relative phase difference between the reference and vibrating object paths. Holograms are made by time-average exposure of three-type recording modes with a laser diode. The phase of vibrating object is extracted from the measurements of Bessel-type fringe irradiances in three kinds of time-average holographic reconstruction. Experimental results of phase and amplitude for a vibrating cantilever object are shown. 相似文献
60.
Quantised phase filters with binary low and high pass amplitude response: the effect of quantisation for scale and rotation input distortions 总被引:1,自引:0,他引:1
Triantafillos Koukoulas Rupert C.D. Young Chris R. Chatwin 《Optics and Lasers in Engineering》2005,43(9):963
In the field of optical pattern recognition, there are a large number of filters that possess identification capabilities for certain kinds of input distortions. The resolution of the spectral components plays an important role in the overall processing time of a correlator that may employ such filters. In this paper, two different techniques are discussed: low pass phase filtering and high pass phase filtering. This is achieved by binarizing the amplitude information which then allows certain frequencies to pass and others to be blocked. Their response to different kinds of input distortions is presented and the effect of phase quantisation is considered in detail. 相似文献