Observation of anapole with dielectric nanoparticles

The possibility of the existence of non-radiating sources has attracted the attention of physicists for many years in different branches of science. One the of the intriguing examples is the so-called anapole moment proposed by Zel'dovich in connection with the radiation-less properties of a toroid solenoid. Furthermore, such electromagnetic configurations were recently suggested to classically describe the nature of dark matter. Recently, we demonstrated that one of the simplest allowing for direct observation of anapole mode in the visible is high-refractive index sub-wavelength nanoparticles. They provide new ways for excitation and investigation of the electro-magnetic properties of such nontrivial excitations.