The Experts below are selected from a list of 249 Experts worldwide ranked by ideXlab platform
Hezhou Wang - One of the best experts on this subject based on the ideXlab platform.
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twin Defect modes in one dimensional photonic crystals with a single negative Material Defect
Applied Physics Letters, 2006Co-Authors: Yongzhu Chen, Jianwen Dong, Hezhou WangAbstract:Twin Defect modes are found in one-dimensional photonic crystals stacking with single- negative-permittivity and single-negative-permeability media layers and a single-negative Defect. The frequency interval of the two Defect modes can be changed by varying the thickness of the Defect layer or the thickness ratio of the two stacking layers. Conditions for the emergence of such twin Defect modes only relate to the phase thicknesses of the Defect layer and the two stacking layers. In addition, the electric fields at the frequencies of the Defect modes are strongly localized at the interfaces between the Defect layer and its adjacent layers.
Yongzhu Chen - One of the best experts on this subject based on the ideXlab platform.
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twin Defect modes in one dimensional photonic crystals with a single negative Material Defect
Applied Physics Letters, 2006Co-Authors: Yongzhu Chen, Jianwen Dong, Hezhou WangAbstract:Twin Defect modes are found in one-dimensional photonic crystals stacking with single- negative-permittivity and single-negative-permeability media layers and a single-negative Defect. The frequency interval of the two Defect modes can be changed by varying the thickness of the Defect layer or the thickness ratio of the two stacking layers. Conditions for the emergence of such twin Defect modes only relate to the phase thicknesses of the Defect layer and the two stacking layers. In addition, the electric fields at the frequencies of the Defect modes are strongly localized at the interfaces between the Defect layer and its adjacent layers.
Chengguang Fan - One of the best experts on this subject based on the ideXlab platform.
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Study of two-wave-mixing interferometric method in ultrasonic detection using BSO crystal
2012 IEEE International Conference on Mechatronics and Automation ICMA 2012, 2012Co-Authors: Shitu Luo, Yukun Luo, Yanling Wang, Chengguang FanAbstract:Testing of the ultrasonic signal is an important matter in laser ultrasonic field. Because of the weakness of the surface vibration caused by ultrasonic, common methods can hardly satisfy the industry application commands. In this paper, a noncontact method, based on two-wave-mixing and the optical adaptivity of photorefractive crystals, is presented to detect the ultrasonic signal on a rough surface. The photorefractive effect and two-wave-mixing characteristics of photorefractive crystals are introduced, followed by the desi gn of ultrasonic signal testing system using a photorefractive crystal, including the stray light collection, crystal protection from high voltage and noise suppression of optical maser. Finally, experiments are carried out to verify the performance of the system. The results show the ability of the system in ultrasonic vibration detection on a few? kinds of rough surfaces and Material Defect evaluation.
Ping Jiang - One of the best experts on this subject based on the ideXlab platform.
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acoustic confinement and waveguiding in two dimensional phononic crystals with Material Defect states
Journal of Applied Physics, 2014Co-Authors: Yinggang Li, Tianning Chen, Xiaopeng Wang, Ping JiangAbstract:In this paper, we present the theoretical investigation of acoustic confinement and waveguiding in two-dimensional phononic crystals with Material Defect states. In contrast to the typical formation pattern of Defect states, the proposed Material Defect states are created by replacing single cylinder in the core center or one row of cylinders in the perfect phononic crystal with different Material cylinders. The dispersion relations and the power transmission spectra are studied by using the finite element method in combination with a supercell technique. With the introduction of Material Defects into perfect phononic crystals, Defect states and bands appear, elastic waves of specific frequencies are localized in the point Defects or along the line Defects, respectively. The displacement fields of the eigenmodes are carried out to further intuitively illustrate the acoustic confinement and waveguiding in the Material Defect states phononic crystals. Furthermore, the effects of the Material parameters of Defects on the point Defect states and waveguiding are further explored numerically. Numerical results show that, the location and number of Defect states can be efficiently modulated by the Material parameters of Defects. The Material Defect states are more sensitive to the density parameters than the elastic constants when the elastic modulus of the Defects is far higher than that of matrix.
Jianwen Dong - One of the best experts on this subject based on the ideXlab platform.
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twin Defect modes in one dimensional photonic crystals with a single negative Material Defect
Applied Physics Letters, 2006Co-Authors: Yongzhu Chen, Jianwen Dong, Hezhou WangAbstract:Twin Defect modes are found in one-dimensional photonic crystals stacking with single- negative-permittivity and single-negative-permeability media layers and a single-negative Defect. The frequency interval of the two Defect modes can be changed by varying the thickness of the Defect layer or the thickness ratio of the two stacking layers. Conditions for the emergence of such twin Defect modes only relate to the phase thicknesses of the Defect layer and the two stacking layers. In addition, the electric fields at the frequencies of the Defect modes are strongly localized at the interfaces between the Defect layer and its adjacent layers.
