Scientists may have discovered a revolutionary new way to confine electromagnetic energy and prevent it from leaking.
The "radical" new theory could help prevent energy loss in future technology, lead to breakthroughs in quantum computers and laser technology, and even explain the nature of dark matter in our universe, according to a news release from Australian National University. The theory is considered radical because it contradicts a "fundamental tenant" of electrodynamics, which is that accelerated charges birth electromagnetic radiation.
"Ever since the beginning of quantum mechanics people have been looking for a configuration which could explain the stability of atoms and why orbiting electrons do not radiate," said Andrey Miroshnichenko from The Australian National University.
The absence of radiation is believed to be caused by a current being divided between two different components: a conventional electric dipole and a toroidal dipole. These dipoles produce identical fields when at a distance, but if the poloidal current configurations are out of phase the radiation will be cancelled out.
The researchers tested their new theory using single silicon nanodiscs between 160 and 310 nanometres in diameter that could be made "invisible" when their scattering of visible light was canceled out in a type of excitation referred to as an "anapole."
The seeds of the new theory were planted when the researchers were attempting to explain differences between two different mathematical descriptions of radiation: one based on Cartesian multipoles and the other on vector spherical harmonics.
"The two gave different answers, and they shouldn't. Eventually we [realized] the Cartesian description was missing the toroidal components," Miroshnichenko said. "We [realized] that these toroidal components were not just a correction, they could be a very significant factor."
Miroshnichenko pointed out the confined energy of anapoles could aid in the development of nanolasers, or "spasers," as well as efficient X-ray lasers by high-order harmonic generation.
