Chiral Phase Change Nanomaterials

TL;DR

This paper introduces a new class of scalable, intrinsically chiral phase change nanomaterials that enable high-speed, reversible control of optical chirality, combining wavelength tunability and dynamic responsiveness at the nanoscale.

Contribution

It presents a novel fabrication method for intrinsically chiral nanomaterials with dynamic control of chirality at high speeds, advancing the field of chiral nanophotonics.

Findings

Achieved high-speed switching of chirality over 50,000 cycles

Demonstrated wavelength tunability through geometric manipulation

Characterized optical properties using Mueller Matrix and ellipsometry

Abstract

Chiral nanostructures offer the ability to respond to the vector nature of a light beam at the nanoscale. While naturally chiral materials offer a path towards scalability, engineered structures offer a path to wavelength tunability through geometric manipulation. Neither approach, however, allows for temporal control of chirality. Therefore, in the best of all worlds, it is crucial to realize chiral materials that possess the quality of scalability, tailored wavelength response, and dynamic control at high speeds. Here, a new class of intrinsically chiral phase change nanomaterials (PCNMs) is proposed and explored, based on a scalable bottom-up fabrication technique with a high degree of control in three dimensions. Angular resolved Mueller Matrix and spectroscopic ellipsometry are performed to characterize the optical birefringence and dichroism, and a numerical model is provided to explain the origin of optical activity. This work achieves the critical goal of demonstrating high-speed dynamic switching of chirality over 50,000 cycles via the underlying PCNM.