Nonradiating sources for efficient wireless power transfer

Esmaeel Zanganeh,Elizaveta Nenasheva,Mingzhao Song,Polina Kapitanova,Adrià Canós Valero,Andrey Evlyukhin,Andrey Miroshnichenko,Alexander S Shalin

doi:10.1515/nanoph-2021-0378

Abstract

Abstract Nonradiating sources of energy realized under a wave scattering on high-index dielectric nanoparticles have attracted a lot of attention in nano-optics and nanophotonics. They do not emit energy to the far-field, but simultaneously provides strong near-field energy confinement. Near-field wireless power transfer technologies suffer from low efficiency and short operation distance. The key factor to improve efficiency is to reduce the radiation loss of the resonators included in the transmitter and receiver. In this paper, we develop a wireless power transfer system based on nonradiating sources implemented using colossal permittivity dielectric disk resonator and a subwavelength metal loop. We demonstrate that this nonradiating nature is due to the hybrid anapole state originated by destructive interference of the fields generated by multipole moments of different parts of the nonradiating source, without a contribution of toroidal moments. We experimentally investigate a wireless power transfer system prototype and demonstrate that higher efficiency can be achieved when operating on the nonradiating hybrid anapole state compared to the systems operating on magnetic dipole and magnetic quadrupole modes due to the radiation loss suppression.

Highlights

Rapid development of all-dielectric nanostructures has provided a new platform for nano-optics and photonics
We experimentally investigate a wireless power transfer system prototype and demonstrate that higher efficiency can be achieved when operating on the nonradiating hybrid anapole state compared to the systems operating on magnetic dipole and magnetic quadrupole modes due to the radiation loss suppression
The goal of this study is to develop a novel approach for highly-efficient near-field wireless power transfer (WPT) via utilization of an NR source based on hybrid anapole state with strongly suppressed far-field radiation

Summary

Introduction

Rapid development of all-dielectric nanostructures has provided a new platform for nano-optics and photonics. The main mechanism to manipulate and control the light propagation at the nanoscale is based on the mode interference and electromagnetic field enhancement of optical resonators made of high-index dielectric materials. Different approaches to manipulate the light–matter interaction, such as engineering dielectric nanostructures with plasmonic materials [1], nanoparticle crystals [2], have been demonstrated so far [3, 4]. An NR source can be defined as a special kind of electromagnetic state that does not emit energy to the far-field region, but simultaneously provides strong near-field energy confinement [5]. Owing to the nonexistence theorem [13], perfect BICs cannot occur in isolated photonic structures, where only the former (anapole states) can lead to far field suppression.

Objectives

Methods

Conclusion