Magnetically Tunable Chirality in 2D Liquid Crystalline WS2 Nanocomposites

TL;DR

This paper reports the discovery of magnetically tunable optical chirality in liquid crystalline WS2 nanocomposites, enabling control over their optical properties for potential applications in optoelectronics and photovoltaics.

Contribution

It introduces the first liquid crystalline WS2 nanocomposites with magnetically switchable chirality and demonstrates their tunable optical properties in various solvents.

Findings

Chirality can be switched ON/OFF with a magnetic field of +/-1.5T.

Wavelength range for chirality switching can be tuned by solvent choice.

Nanocomposites exhibit significant birefringence and reconfigurable optical chirality.

Abstract

The first observation of tungsten disulfide liquid crystalline nanocomposites in dispersions of liquid phase-exfoliated flakes is demonstrated in a range of organic solvents. The nanocomposites demonstrate significant birefringence and reconfigurable optical chirality as observed in the linear and circular dichroism measurements respectively. Under an applied magnetic field of +/-1.5T the chirality can be switched ON/OFF, while the wavelength range for switching can be tuned from large to narrow range by the proper selection of the host solvent. In combination with photoluminescence capabilities of WS2, this opens a pathway to a wide variety of applications, such as deposition of highly uniform films over large areas for photovoltaic devices, as shown here.