Photonic jets from resonantly excited transparent dielectric microspheres

We report on the theoretical investigations of the near-field diffraction patterns from micrometer-sized spherical dielectric particles illuminated by a light wave upon the excitation of morphology-dependent resonances in the internal field. The specific spatial area, which constitutes the so-called photonic jet (PJ), is studied. The longitudinal and transverse dimensions of the PJ are calculated along with its peak intensity as a function of the distance from a particle. The numerical calculations show that at a resonance depending on its quality factor, the PJ can “stick” to the particle; its intensity can increase to a several orders of magnitude, and its width can decrease but mostly near the microsphere surface. The average length of the PJ remains nearly unchanged.