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All-optical steering of the nonlinear interactions between multiple spatial solitons can be performed in an isotropic photoisomerization polymer, by propagating an external control beam in perpendicular direction. Fusing, giving birth to another new soliton, and transferring energy can take place in the interactions of signal beams, which can be achieved by changing the incident position of the control beam, the initial relative phase and the power ratio between the signal beams and the control beam. These phenomena are physically explained, and they have significantly potential applications in optical signal readdressing, logic gating, and all-optical switching, etc. 相似文献
43.
Kenichi Masuda Atsushi Tate Mariko Ishida Takanori Suzuki Hiroyuki Tsuda 《Optical Review》2006,13(4):184-188
We propose a beam steering type optical switch employing a phase shifter. It consists of collimating waveguide mirrors, an
arrayed-waveguide which has deep trenches incorporating polymer materials, and input/output waveguides. The incident light
is guided to the front mirror, where it is then collimated, and input to the arrayed waveguide. The number of trenches filled
with polymer linearly increases in order. The refractive index of the polymer can be controlled with temperature, and the
propagation direction of the output light from the arrayed waveguide can also be controlled. A switch with 15 waveguides in
the array has been fabricated. The chip size is about 2:5 × 9:0 mm2, the insertion loss is 10 dB, and the extinction ratio is about 10–13 dB. 相似文献
44.
为提高航空图像的空间分辨率, 提出一种基于多相组重建的超分辨率算法. 融合图像间的互补信息, 将多帧低分辨率图像作为图像基, 参考帧分解为多相组, 利用差异采样特性构建图像基与参考帧之间的的多相组线性关系重建得到高分辨率图像的多项组, 经图像多相分解逆变换获得融合的高分辨率图像. 根据该融合图像的局部内容和结构信息自适应调整控制核核函数, 应用改进的控制核回归算法去除图像模糊和噪声得到清晰的超分辨率图像. 与传统算法相比, 该算法无需图像配准和迭代过程, 计算效率极大地提高. 实验结果表明, 本文算法能够有效提高航空图像的空间分辨率, 在定量评价指标和主观视觉效果方面都有显著提高. 相似文献
45.
量子关联是量子信息、量子计算与量子计量领域的重要资源, 在量子纠缠和贝尔非局域性中, 两子系统起着同等关键的作用, Einstein-Podolsky-Rosen (EPR)量子引导关联的强度介于量子纠缠和贝尔非局域性之间, 对单向EPR量子引导关联而言两子系统的作用不对等. 本文研究了双模Bose-Hubbard模型中模间量子关联的动态特性, 揭示了EPR量子引导关联的取向对系统初态模间交换对称性的依赖关系. 根据Hillery-Zubairy纠缠判据以及基于最大平均量子Fisher信息的纠缠判据考察了系统初态对模间量子纠缠演化规律的影响. 如果模间耦合强度远大于同一势阱内粒子间的相互作用, 初始处于SU(2)相干态的系统在具有确定的两子系统交换对称性的条件下, 其量子关联呈现简单的周期性演化规律; 当这种对称性破缺时, 模间量子关联的演化呈现较复杂的崩塌与回复现象. 相似文献
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48.
Elias Riedel Grding Nicolas Schwaller Chun Lam Chan Su Yeon Chang Samuel Bosch Frederic Gessler Willy Robert Laborde Javier Naya Hernandez Xinyu Si Marc-Andr Dupertuis Nicolas Macris 《Entropy (Basel, Switzerland)》2021,23(7)
We propose the first correct special-purpose quantum circuits for preparation of Bell diagonal states (BDS), and implement them on the IBM Quantum computer, characterizing and testing complex aspects of their quantum correlations in the full parameter space. Among the circuits proposed, one involves only two quantum bits but requires adapted quantum tomography routines handling classical bits in parallel. The entire class of Bell diagonal states is generated, and several characteristic indicators, namely entanglement of formation and concurrence, CHSH non-locality, steering and discord, are experimentally evaluated over the full parameter space and compared with theory. As a by-product of this work, we also find a remarkable general inequality between “quantum discord” and “asymmetric relative entropy of discord”: the former never exceeds the latter. We also prove that for all BDS the two coincide. 相似文献
49.
M. Dinkelmann M. Wächter G. Sachs 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(3):237-255
Heat input reduction by appropriate, optimal trajectory control is considered for the range cruise and the return-to-base cruise of a hypersonic vehicle propelled by a turbo/ram jet engines combination. A mathematical model is developed for describing the unsteady heat transfer through the thermal protection system. This model is coupled to the model of the dynamics of the vehicle. An efficient optimization technique is applied for constructing a solution for the two cruise problems. The results show that significant heat input reductions can be achieved with only a small penalty in fuel consumption. 相似文献
50.
In this paper, we present a novel technique for high precision optical beam steering of optical phased arrays (OPA) using mixed weighting method. Optimal OPA parameters are determined to obtain the best beam directivity by minimizing the main lobe width and eliminating grating lobes of the far field diffraction pattern. The quantitative analysis for a fibre-type optical phased array is given. The calculation results demonstrate that the grating lobe level can be distinctly reduced from 80% to 20% of the main lobe level. Thus, the mixed weighting technique proposed in this paper can substantially improve the beam steering efficiency and the beam quality. 相似文献