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arXiv · 0903.1693

Direct Observation of Photonic Jets and Corresponding Backscattering Enhancement at Microwave frequencies

Li Zhao·C. K. Ong
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Abstract

We experimentally verified the phenomena of photonic jets generated by plane-electromagnetic-wave-illuminated dielectric micro-cylinders with diameter comparable to the corresponding wavelength at microwave frequencies. Using a home-made 2D spatial field mapping system, we carried out a point-by-point measurement of both phase and intensity of spatial electric field distribution inside and around scattering cylinders, providing a clear complete electromagnetic field picture for these phenomena. Correspondingly, the theoretically predicted super-enhancement of the backscattering induced by small particles of deeply-subwavelength size located within the photonic jets was also confirmed. Our measurements agreed well with the numerical simulations, indicating that the photonic jets indeed can provide a promising powerful way for deeply subwavelength detection and imaging.

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Li Zhao, C. K. Ong. 2009-03-10. Direct Observation of Photonic Jets and Corresponding Backscattering Enhancement at Microwave frequencies. https://doi.org/10.1063/1.3151706

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