We establish a new approach for pump-probe simulations of metallic metamaterials coupled to the gain materials. It is of vital importance to understand the mechanism of the coupling of metamaterials with the gain medi...
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We establish a new approach for pump-probe simulations of metallic metamaterials coupled to the gain materials. It is of vital importance to understand the mechanism of the coupling of metamaterials with the gain medium. Using a four-level gain system, we have studied light amplification of arrays of metallic split-ring resonators with a gain layer underneath. We find that the differential transmittance ΔT/T can be negative for split-ring resonators on the top of the gain substrate, which is not expected, and ΔT/T is positive for the gain substrate alone. These simulations agree with pump-probe experiments and can help to design new experiments to compensate for the losses of metamaterials.
This paper has studied spontaneous symmetry breaking (SSB) phenomenon in two types of two-channel asymmetric simple exclusion processes (ASEPs). One common feature of the two systems is that interactions for each spec...
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This paper has studied spontaneous symmetry breaking (SSB) phenomenon in two types of two-channel asymmetric simple exclusion processes (ASEPs). One common feature of the two systems is that interactions for each species of particle happen at only one site, and the system reduces to two independent ASEPs when interaction vanishes. It is shown that with the weakening of interaction, the SSB is suppressed. More interestingly, the SSB disappears before the interaction is eliminated. Our work thus indicates that local interaction has to be strong enough to produce SSB. The mean-field analysis has been carried out, and the results are consistent with the simulation ones.
We present a novel algorithm for point pattern matching by means of spectra of directed graphs. Given a feature point-set, we construct a weighted directed graph and skew-symmetric matrix associated with the graph. By...
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We present a novel algorithm for point pattern matching by means of spectra of directed graphs. Given a feature point-set, we construct a weighted directed graph and skew-symmetric matrix associated with the graph. By using spectral decomposition of the matrix, we give a spectral representation of the feature points with half of the eigenvectors. We theoretically analyze that our method can well deal with the matching problem under affine transformation. The expreiments applied to synthetic data and real-world images show the effectiveness of our method.
The method of splitting a plane-wave finite-difference time-domain （SP-FDTD） algorithm is presented for the initiation of plane-wave source in the total-field / scattered-field （TF/SF） formulation of high-order sy...
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The method of splitting a plane-wave finite-difference time-domain （SP-FDTD） algorithm is presented for the initiation of plane-wave source in the total-field / scattered-field （TF/SF） formulation of high-order symplectic finite- difference time-domain （SFDTD） scheme for the first time. By splitting the fields on one-dimensional grid and using the nature of numerical plane-wave in finite-difference time-domain （FDTD）, the identical dispersion relation can be obtained and proved between the one-dimensional and three-dimensional grids. An efficient plane-wave source is simulated on one-dimensional grid and a perfect match can be achieved for a plane-wave propagating at any angle forming an integer grid cell ratio. Numerical simulations show that the method is valid for SFDTD and the residual field in SF region is shrinked down to -300 dB.
Compressive imaging is an important application of the compressive sensing theory. This paper proposes a novel compressive double-lens imaging method with circulant-circulant-block phase mask matrices to implement ima...
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Compressive imaging is an important application of the compressive sensing theory. This paper proposes a novel compressive double-lens imaging method with circulant-circulant-block phase mask matrices to implement image acquisition. Simulation results show that the novel phase mask matrices can effectively capture the information of image with a significant reduction of measurements. For the standard Lena and Cameraman images both with 64-by-64 pixels, the number of measurements is only 58.6% of all pixels, and the reconstructed signal-to-noise ratios exceed 26 dB and 30 dB, respectively. The new research provides more supports for deterministic measurement in the application of compressive imaging, which has more advantages than toeplitz and circulant matrices, reduces the difficulty and cost of the physical realization and provides some theoretical, computing and technical supports for new design of camera.
Power quality is the guide to the power of equipment malfunction or cannot work normally voltage. Rapid use, to the electric power quality caused serious, destruction and pollution power quality, produce the voltage w...
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Power quality is the guide to the power of equipment malfunction or cannot work normally voltage. Rapid use, to the electric power quality caused serious, destruction and pollution power quality, produce the voltage wave and so on many kinds of power quality problems, to the user and power supply party bring huge economic loss "at the same time to plan. Microprocessor as the core of the intelligent precision equipment to the electric power quality put forward higher requirement, how to effectively can quality problem, improve the quality of power become the electric power industry research hotspot and focus of power quality inspection Richard and improve the quality of power, the prerequisite and basis of only fast. The correct detection and recognition of the electrical energy to take the right management measures improve the quality of power;reduce the loss of power quality problems.
A high-order symplectic FDTD (SFDTD) framework for solving the time-dependent Schrödinger equation is established. The third-order symplectic integrators and fourth-order collocated differences are employed in th...
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A high-order symplectic FDTD (SFDTD) framework for solving the time-dependent Schrödinger equation is established. The third-order symplectic integrators and fourth-order collocated differences are employed in the time and space domains, respectively. The stabilities and numerical dispersions of FDTD(2,2), higher-order FDTD(2,4), and SFDTD(3,4) schemes are analyzed. We found that the stability limit of the SFDTD(3,4) scheme can be larger than that of the traditional FDTD(2,2) method through careful optimization of symplectic integrators. Moreover, the SFDTD(3,4) scheme and the FDTD(2,4) approach show better numerical dispersions than the traditional FDTD(2,2) method.
Phase retrieval technique using the directly measured intensity distribution to recover phase information and reconstruct the wave function is an important area of optics and image processing. Taking advantage of the ...
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Phase retrieval technique using the directly measured intensity distribution to recover phase information and reconstruct the wave function is an important area of optics and image processing. Taking advantage of the existing phase retrieval based on transport equation of intensity, the light propagation model consistent with the principle of general camera images in natural light conditions is established, the corresponding optical data collection platform is designed and a phase retrieval method in this new model is derived. Real experimental results verify that this new phase retrieval method is reasonable and correct. The application of traditional phase retrieval algorithm on transport equation of intensity is extended to the holographic display and other macro-areas.
Brain-computer interface (BCI) which transforms signals from the brain into control signals can help people with disabilities communicate with others. In this paper, posteriori probability support vector machine (PPSV...
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Nowadays, the Human Computer Interaction (HCI) developments improve the research of EOG. In this paper, A new EOG-based HCI system for multimedia control is designed and implemented. A special headset named Mindset is...
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