Transverse Kerker effect of localized electromagnetic sources

TL;DR

This paper introduces the transverse Kerker effect for localized electromagnetic sources, demonstrating directional emission control using dielectric antennas, with analytical conditions and experimental validation, advancing nanophotonics and quantum optics applications.

Contribution

It presents the concept of transverse Kerker effect for localized sources, deriving analytical conditions, and experimentally validating the effect for magnetic dipole emitters.

Findings

Directional emission along dipole moments achieved

Suppression of radiation perpendicular to dipole moments

Purcell enhancement observed in dielectric antennas

Abstract

Transverse Kerker effect is known by the directional scattering of an electromagnetic plane wave perpendicular to the propagation direction with nearly suppression of both forward and backward scattering. Compared with plane waves, localized electromagnetic emitters are more general sources in modern nanophotonics. As a typical example, manipulating the emission direction of a quantum dot is of virtue importance for the investigation of on-chip quantum optics and quantum information processing. Herein, we introduce the concept of transverse Kerker effect of localized electromagnetic sources utilizing a subwavelength dielectric antenna, where the radiative power of magnetic, electric and more general chiral dipole emitters can be dominantly directed along its dipole moment with nearly suppression of radiation perpendicular to the dipole moments. Such transverse Kerker effect is also associated with Purcell enhancement mediated by electromagnetic multipolar resonances induced in the dielectric antenna. Analytical conditions of transverse Kerker effect are derived for the magnetic dipole, electric dipole and chiral dipole emitters. We further provide microwave experiment validation for the magnetic dipole emitter. Our results provide new physical mechanisms to manipulate the emission properties of localized electromagnetic source which might facilitate the on-chip quantum optics and beyond.