基于机器视觉的车辆保险盒在线检测研究

摘要: 车辆保险盒作为汽车电控系统中的一个重要的元器件,其质量好坏直接影响汽车的性能,传统的车辆保险盒检测主要依靠人工检测,检测费时费力,针对该问题,提出一种基于视觉的车辆保险盒在线检测方法,分析了产品图像校正到标准模板图像的位置误差,采用SURF(Speeded Up Robust Feature)算法和平面单应性理论将待检产品图像变换到标准模板位置,利用颜色直方图匹配和模板匹配完成保险盒上元件的检测。实验结果证明,该方法检测效率高,稳定可靠,能够满足在线检测的要求,具有一定实用价值。     

Laser-polarization-dependent spontaneous emission of the zero phonon line from single nitrogen vacancy center in diamond

We investigate spontaneous emission properties and control of the zero phonon line （ZPL） from a diamond nitrogen- vacancy （NV） center coherently driven by a single ellipfically polarized control field. We use the Schrrdinger equation to calculate the probability amplitudes of the wave function of the coupled system and derive analytical expressions of the spontaneous emission spectra. The numerical results show that a few interesting phenomena such as enhancement, narrowing, suppression, and quenching of the ZPL spontaneous emission can be realized by modulating the polarization- dependent phase, the Zeeman shift, and the intensity of the control field in our system. In the dressed-state picture of the control field, we find that multiple spontaneously generated coherence arises due to three close-lying states decaying to the same state. These results are useful in real experiments.     

Bright Solitons in an Atomic Tunnel Array with Either Attractive or Repulsive Atom-Atom Interactions

Taking a coherent state representation, we derive the nonlinear Schroedinger-type differential-difference equations from the quantized model of an array of traps containing Bose-Einstein condensates and linked by the tunnelling process among the adjacent traps. It is shown that no matter whether two-body interactions among atoms are repulsive or attractive, a nearly uniform atom distribution can evolve into a bright soliton-type localized ensemble of atoms and a lump of atom distribution can also be smeared out by redistributing atoms among traps under appropriate initial phase differences of atoms in adjacent traps. These two important features originate from the tailoring effect of the initial phase conditions in coherent tunnelling processes, which differs crucially from the previous tailoring effect coming mainly from the periodicity of optical lattices.     

Continuous-Wave Four-Wave Mixing via Electromagnetically Induced Transparency in Double-∧ Configuration

We investigate continuous-wave four-wave mixing via electromagnetically induced transparency in double-∧ con-figuration by using Schroedinger-Maxwell formalism. We derive the corresponding explicit analytical expressions.     

Deterministic Generation of Quantum State Transfer Between Spatially Separated Single Molecule Magnets

We propose a new scheme for realizing deterministic quantum state transfer （QST） between two spatially separated single molecule magnets （SMMs） with the framework of cavity quantum eleetrodynamics （QED）. In the present scheme, two SMMs are trapped in two spatially separated optical cavities coupled by an optical fiber. Through strictly numerically simulating, we demonstrate that our scheme is robust with respect to the SMMs＇ spontaneous decay and fiber loss under the conditions of dispersive SMMs-field interaction and strong coupling of cavity fiber. In addition, we also discuss the influence of photon leakage out of cavities and show that our proposal is good enough to demonstrate the generation of QST with high fidelity utilizing the current experimental technology. The present investigation provides research opportunities for realizing QST between solid-state qubits and may result in a substantial impact on the progress of solid-state-based quantum communications network.     

Deterministic generation of Greenberger-Horne-Zeilinger and W states for three distant atoms via adiabatic passage

We propose two schemes for generating Greenberger-Horne-Zeilinger and W states of three distant atoms.In the present schemes,the atoms are individually trapped in three spatially separated optical cavities coupled by two optical fibres.Performing an adiabatic passage along dark states,the population of cavities and fibres excited is negligible under certain conditions.In addition,the spontaneous decay of atoms is also efficiently suppressed based on our proposals.Furthermore,the discussion about the entanglement fidelity is given and we point out that our schemes work robustly with small fluctuations of experimental parameters.     

单个原子的二模有效Raman理论研究

研究了单个原子或离子与两束激光量子场相互作用的非线性系统．首先提出描述一次涉及2k（k=1，2，3，…）个光子的光强相关耦合Raman过程的普适模型，然后利用作者发展的一种求解各种非线性Jaynes-Cummings模型的系统方法，精确求解了该普适模型，得到了它的能量本征值和本征矢、演化算符、光子数算符和原子反转算符的解析表达式 关键词：     

单个囚禁离子的Jaynes—Cummings模型

Ｃｉｒａｃ等人证明处于驻波光场波节处的单个囚禁两能级离子的动力学由Ｊａｙｎｅｓ－Ｃｕｍ－ｍｉｎｇｓ（Ｊ－Ｃ）模型描述。本文旨在推广这一结论。通过引入穿衣态描述，证明处于驻波光场中任意位置时，单个囚禁的两能级离子的动力学仍由相同模型描述。     

等离子体简并与近简并四波混频理论——反射光栅位形

系统研究波波相互作用形成反射光栅情况下的等离子体简并与近简并四波混频理论,导出普适四波非线性耦合方程组,并在任意复耦合系数情况下求出其精确解析解。 关键词：     

Matched Ultra Slow Optical Solitons in Double-Λ Media

We study the four-wave mixing （FWM） in a double-Λ atomic system where two strong continuous-wave pump lasers and a weak pulsed probe laser produce an FWM generated pulse. We show that both the probe and FWM generated fields may evolve into bright and dark solitons with the same shape and the same ultraslow group velocity.