Ultrathin Terahertz Planar Lenses

TL;DR

This paper presents the design and fabrication of ultrathin terahertz planar lenses that significantly reduce lens thickness using interface phase modulation, enabling compact THz optical systems.

Contribution

The work introduces a novel approach for ultrathin THz lenses based on interface phase modulation of antenna resonance, achieving a thickness of only 100 nm.

Findings

Successfully fabricated 100 nm thick lenses

Demonstrated focusing and imaging capabilities

Paves the way for micro-integrated THz systems

Abstract

Conventional optical components shape the wavefront of propagating light by adjusting the optical path length, which requires the use of rather thick lenses, especially for the adjustment of terahertz (THz) radiation due to its long wavelength. Two ultrathin THz planar lenses were designed and fabricated based on interface phase modulation of antenna resonance. The lens thicknesses were extremely reduced to 100 nm, which is only 1/4000th of the illuminating light wavelength. The focusing and imaging functions of the lenses were experimentally demonstrated. The ultrathin optical components described herein are a significant step toward the development of a micro-integrated THz system.