# Terahertz Chiral Optics with Ordered Carbon Nanotube Architectures

## TL;DR

This paper introduces a novel terahertz chiral optical device using aligned carbon nanotube films, achieving tunable broadband circular dichroism with potential for enhanced performance through multilayer structures.

## Contribution

It presents a new artificial structure based on aligned carbon nanotubes that exhibits tunable broadband circular dichroism in the terahertz range, supported by theoretical simulations.

## Key findings

- Achieved up to 2.8 degrees of circular dichroism in experiments.
- Theoretical models predict up to ~30 degrees of CD with additional CNT layers.
- Behavior of the device is reciprocal and tunable across a broad spectrum.

## Abstract

Chiral optical terahertz (THz) devices have significant technological implications for telecommunications, spectroscopy, and sensing. Engineering tunable, broadband, and cost-effective THz chiral materials has long been recognized as a challenging endeavor and has been the bottleneck hindering the full exploitation of the THz spectrum. Here, we present an artificial structure based on aligned carbon nanotube films that exhibit a tunable broadband circular dichroism (CD) up to 2.8 degrees. Its behavior is reciprocal. The developed theoretical simulations are in agreement with the experiments and predict a further increase of CD signal up to ~30 degrees when more CNT layers are added.