In the plasma sheath a narrow plasma channel generated by ultraintense laser pulses is simplified as a special cylindrical and hollow plasma waveguide with the infinite thickness of the plasma cladding. The electromag...In the plasma sheath a narrow plasma channel generated by ultraintense laser pulses is simplified as a special cylindrical and hollow plasma waveguide with the infinite thickness of the plasma cladding. The electromagnetic wave （EM） propagation properties of the plasma channel near the cutoff and far from the cutoff are considered. Theoretical analysis shows that TE0m and TM0m and hybrid modes emerge in the plasma channel, which is influenced by the normalized frequency parameter B and numerical aperture NA. The cutoffs of the various modes are approximated. Single-mode operation is possible without a high-frequency limitation in the channel.展开更多
We propose the practical realization of a shrinking device by using layered structures of homogeneous isotropic materials.By mimicking the shrinking device with concentric alternating thin layers of isotropic dielectr...We propose the practical realization of a shrinking device by using layered structures of homogeneous isotropic materials.By mimicking the shrinking device with concentric alternating thin layers of isotropic dielectrics,the permittivity and the permeability in each isotropic layer can be properly determined from the effective medium theory in order to achieve the shrinking effect.The device realized by multilayer coating with dielectrics is validated by TE wave simulation,and good shrinking performance is demonstrated with only a few layers of homogeneous isotropic materials.展开更多
Using the concept of optical transformation, we report on an amplifying device, which can make an arbitrary object enlarged. Its potential application to small object identification and detection is foreseeable. The c...Using the concept of optical transformation, we report on an amplifying device, which can make an arbitrary object enlarged. Its potential application to small object identification and detection is foreseeable. The cylindrical anisotropic amplifying shell could be mimicked by radially symmetrical ＂sectors＂ alternating in composition between two profiles of isotropic dielectrics; the permittivity and permeability in each ＂sector＂ can be properly determined by the effective medium theory. Both the magnetic and nonmagnetic amplifying devices are validated by full-wave finite element simulations. Good amplifying performance is observed.展开更多
Based on the effective medium theory, the triangular ground plane cloak can be realized by thin layered systems. Two solutions of parameter setting of the layered cloak are suggested to demonstrate the invisibility pe...Based on the effective medium theory, the triangular ground plane cloak can be realized by thin layered systems. Two solutions of parameter setting of the layered cloak are suggested to demonstrate the invisibility performance of a hybrid incoming wave. The hybrid parameters are derived from the equivalent of both anisotropies of permittivity and permeability to the Mternating layers. The performance of the designed layered cloak is validated by both TM and TE wave simulations with near-field distributions and average scattering power outflows on an observation semicircle. From the simulation results, the layered cloak with both hybrid parameters and improved hybrid parameters can reflect the incoming TM/TE waves in a specular direction, and the latter behaves with a better overall invisibility performance.展开更多
基金supported by National Natural Science Foundation of China(No.60971122)the Jiangshu Province Science Foundation(No.BK2011727)the Open Research Program in China's State Key Laboratory of Millimeter Waves(No.K201103)
文摘In the plasma sheath a narrow plasma channel generated by ultraintense laser pulses is simplified as a special cylindrical and hollow plasma waveguide with the infinite thickness of the plasma cladding. The electromagnetic wave （EM） propagation properties of the plasma channel near the cutoff and far from the cutoff are considered. Theoretical analysis shows that TE0m and TM0m and hybrid modes emerge in the plasma channel, which is influenced by the normalized frequency parameter B and numerical aperture NA. The cutoffs of the various modes are approximated. Single-mode operation is possible without a high-frequency limitation in the channel.
基金Project supported by the National Natural Science Foundation of China (Grant No. 60971122)the Natural Science Foundation of Jiangsu Province of China (Grant No. BK2011727)+1 种基金the Open Research Program in China’s State Key Laboratory of Millimeter Waves (Grant No. K201103)the Funding of Graduate Innovation Center in NUAA (Grant No. kfjj20110216)
文摘We propose the practical realization of a shrinking device by using layered structures of homogeneous isotropic materials.By mimicking the shrinking device with concentric alternating thin layers of isotropic dielectrics,the permittivity and the permeability in each isotropic layer can be properly determined from the effective medium theory in order to achieve the shrinking effect.The device realized by multilayer coating with dielectrics is validated by TE wave simulation,and good shrinking performance is demonstrated with only a few layers of homogeneous isotropic materials.
基金Project supported by the Open Research Program in State Key Laboratory of Millimeter Waves,China (Grant No.K200802)the National Natural Science Foundation of China (Grant No.61302048)the Priority Academic Program Development of Jiangsu Provincial Higher Education Institutions,China
文摘Using the concept of optical transformation, we report on an amplifying device, which can make an arbitrary object enlarged. Its potential application to small object identification and detection is foreseeable. The cylindrical anisotropic amplifying shell could be mimicked by radially symmetrical ＂sectors＂ alternating in composition between two profiles of isotropic dielectrics; the permittivity and permeability in each ＂sector＂ can be properly determined by the effective medium theory. Both the magnetic and nonmagnetic amplifying devices are validated by full-wave finite element simulations. Good amplifying performance is observed.
基金supported partly by the Open Research Program in State Key Laboratory of Millimeter Waves of China (Grant No. K201103)partly by the National Natural Science Foundation of China (Grant No. 60971122)partly by the Natural Science Foundation of Jiangsu Province of China (Grant No. BK2011727)
文摘Based on the effective medium theory, the triangular ground plane cloak can be realized by thin layered systems. Two solutions of parameter setting of the layered cloak are suggested to demonstrate the invisibility performance of a hybrid incoming wave. The hybrid parameters are derived from the equivalent of both anisotropies of permittivity and permeability to the Mternating layers. The performance of the designed layered cloak is validated by both TM and TE wave simulations with near-field distributions and average scattering power outflows on an observation semicircle. From the simulation results, the layered cloak with both hybrid parameters and improved hybrid parameters can reflect the incoming TM/TE waves in a specular direction, and the latter behaves with a better overall invisibility performance.
