Inverse Designed THz Spectral Splitters

TL;DR

This paper demonstrates a 3D printable, low-cost THz spectral splitter using inverse design of diffractive optical elements, capable of dispersing broadband THz radiation at a specified distance with potential applications in spectroscopy and wireless communication.

Contribution

It introduces a novel inverse design method for creating 3D printable THz spectral splitters that are compact and cost-effective, with demonstrated simulation and experimental results.

Findings

Successfully designed and fabricated THz spectral splitters

Validated spectral dispersion with measurements in the 0.5-0.75 THz range

Potential for applications in portable spectroscopy and wireless THz systems

Abstract

This letter reports proof-of-principle demonstration of 3D printable, low-cost, and compact THz spectral splitters based on diffractive optical elements (DOEs) designed to disperse the incident collimated broadband THz radiation (0.5 THz - 0.7 THz) at a pre-specified distance. Via inverse design, we show that it is possible to design such a diffractive optic, which can split the broadband incident spectrum in any desired fashion, as is evidenced from both FDTD simulations and measured intensity profiles using a 500-750 GHz VNA. Due to its straightforward construction without the usage of any movable parts, our approach, in principle, can have various applications such as in portable, low-cost spectroscopy as well as in wireless THz communication systems as a THz demultiplexer.