Enhanced superlens imaging with loss-compensating hyperbolic near-field spatial filter

TL;DR

This paper presents a physical implementation of a loss-compensation scheme using an auxiliary source and spatial filter on a silver superlens, significantly improving near-field imaging beyond the diffraction limit despite losses.

Contribution

It introduces a practical method to enhance superlens imaging by employing a plasmon injection scheme with a near-field spatial filter, avoiding the need for nonlinear effects or gain media.

Findings

Enhanced near-field imaging beyond diffraction limit

Loss compensation achieved with auxiliary illumination and spatial filtering

Object resolution improved in lossy conditions

Abstract

Recently a coherent optical process called plasmon injection ($\Pi$) scheme, which employs an auxiliary source, has been introduced as a new technique to compensate losses in metamaterials. In this work, a physical implementation of the $\Pi$ scheme on a thin silver film is proposed for enhanced superlens imaging. The efficacy of the scheme is illustrated by enhancing near-field imaging deeper beyond the diffraction limit in the presence of absorption losses and noise. The auxiliary source is constructed by a high-intensity illumination of the superlens integrated with a near-field spatial filter. The integrated system enables reconstruction of an object previously unresolvable with the superlens alone. This work elevates the viability of the $\Pi$ scheme as a strong candidate for loss compensation in near-field imaging systems without requiring non-linear effects or gain medium.