An ultra-narrow photonic nanojet generated from a high refractive-index micro-flat-ended cylinder. (2nd April 2020) - Zhou, Song
Abstract: Photonic nanojets (PNJs) generated from high refractive-index micro-flat-ended cylinders is investigated utilizing finite element method. We study the influences of the refractive index of flat-ended cylinders on the properties of PNJs. And find that the flat-ended cylinders with high refractive index can shrink the beam waist of PNJs. Our simulation shows that under 550 nm illumination, the full width at half maximum of the beam waist can reach 70 nm (~ λ /7.8), when the refractive index of the flat-ended cylinder is chosen as n c = 4. The ability of silicon medium used for this high-index micro-flat-ended cylinder for PNJs generation is also demonstrated.