Anapole source based on electric dipole interactions over a low-index dielectric

Pursuing nonradiating sources and radiationless motion for accelerated charged particles has captivated physicists for generations. Nonradiating sources represent intricate current-charge configurations that do not emit radiation beyond their source domain. This study investigates a single nonradiating source comprising a low-index dielectric disk excited by a split-ring resonator. Employing analytical and numerical methods, we demonstrate that this configuration supports an anapole state, exhibiting minimal or no radiation, effectively representing a nonradiating source. The radiation suppression is accomplished through the destructive interference of electric dipoles excited on the metallic and dielectric components of the proposed prototype. Transforming the design into a cost-effective device capable of suppressing radiation, we achieve excellent numerical and experimental agreement, affirming the formation of the anapole state using the lowest-order multipoles. Moreover, the devised anapole device is remarkably compact, constructed from a low-index dielectric, and employs readily available components. As a versatile platform, the proposed device can spearhead anapole research for diverse applications, including sensing, wireless charging, radio frequency identification tags, and other nonlinear applications.