1. Institute of Electromagnetics and Acoustics and Department of Electronic Science, Xiamen University, Xiamen 361005, China 2. Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, China
We present a series of invisibility concentrators with simplified material parameters beyond transformation optics. One of them can achieve the perfect invisible effect at frequencies of Fabry–Pérot resonances, while others have very small scattering. The required materials are feasible in practice. Analytical calculations and numerical simulations confirm the functionalities of these devices.
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Y. Lai, H. Chen, Z. Q. Zhang, and C. T. Chan, Complementary media invisibility cloak that cloaks objects at a distance outside the cloaking shell, Phys. Rev. Lett. 102(9), 093901 (2009) https://doi.org/10.1103/PhysRevLett.102.093901
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Y. Lai, J. Ng, H. Chen, D. Z. Han, J. J. Xiao, Z.Q. Zhang, and C. T. Chan, Illusion optics: The optical transformation of an object into another object, Phys. Rev. Lett. 102(25), 253902 (2009) https://doi.org/10.1103/PhysRevLett.102.253902
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M. M. Sadeghi, S. Li, L. Xu, B. Hou, and H. Chen, Transformation optics with Fabry-Pérot resonances, Sci. Rep. 5(1), 8680 (2015) https://doi.org/10.1038/srep08680
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C. Navau, J. Prat-Camps, O. Romero-Isart, J. I. Cirac, and A. Sanchez, Long-distance transfer and routing of static magnetic fields, Phys. Rev. Lett. 112(25), 253901 (2014) https://doi.org/10.1103/PhysRevLett.112.253901
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J. Prat-Camps, C. Navau, and A. Sanchez, Experimental realization of magnetic energy concentration and transmission at a distance by metamaterials, Appl. Phys. Lett. 105(23), 234101 (2014) https://doi.org/10.1063/1.4903867
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C. Navau, J. Prat-Camps, and A. Sanchez, Magnetic energy harvesting and concentration at a distance by transformation optics, Phys. Rev. Lett. 109(26), 263903 (2012) https://doi.org/10.1103/PhysRevLett.109.263903
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F. Sun and S. He, Transformation inside a Null-space region and a DC magnetic funnel for achieving an enhanced magnetic flux with a large gradient, Prog. Electromagnetics Res. 146, 143 (2014) https://doi.org/10.2528/PIER14031707
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