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

TL;DR

This paper experimentally demonstrates photonic jets generated by dielectric micro-cylinders at microwave frequencies, confirming their role in enhancing backscattering and potential for subwavelength detection and imaging.

Contribution

First experimental verification of photonic jets at microwave frequencies with detailed field mapping and confirmation of backscattering enhancement.

Findings

Photonic jets are generated by dielectric micro-cylinders at microwave frequencies.

Backscattering is significantly enhanced when small particles are within photonic jets.

Experimental results agree well with numerical simulations.

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.