Lighting of a monochromatic scatterer with virtual gain

TL;DR

This paper demonstrates how to control and enhance monochromatic magnetic light emission from a lossless nanosphere using virtual gain and loss concepts, enabling tunable, high-quality light sources at the nanoscale.

Contribution

It introduces a novel method to achieve virtual gain and loss in a lossless nanostructure by shaping incident waveforms, allowing on-demand energy capture and release.

Findings

Nanosphere can emit tunable monochromatic magnetic light.

Virtual gain and loss achieved without material loss.

Potential applications in lab-on-a-chip and nanoscale light sources.

Abstract

In this work, we discuss the scattering features of a dipolar particle made of large refractive index material by employing the concept of virtual gain and virtual loss. The virtual gain and loss can be achieved in a lossless passive nanostructure by shaping the temporal waveform of incident signals in the complex frequency plane. We show that an appropriate tuning of excitation time of the impinging field allows to capture and release the electromagnetic energy on-demand for an arbitrary time scale in a lossless nanosphere. Thus, the nanosphere obliges to emit monochromatic magnetic light which can be tuned throughout the whole visible spectrum by varying the size of the nanosphere. This proposal may find fruitful applications in lab-on-a-chip technologies and the realization of monochromatic sectoral multipole light source with a large quality factor at nanoscale level.