# Characterization of Aligned Polymers Using the Spin Hall Effect of Light

## TL;DR

This paper introduces a new method using the spin Hall effect of light to study aligned polymer films, showing it is more sensitive and precise than existing techniques.

## Contribution

The paper introduces the spin Hall effect of light as a novel, high-sensitivity method for characterizing polymer alignment.

## Key findings

- UV irradiation enhances polymer chain alignment, with alignment increasing with irradiation time.
- SHEL provides a 30 dB signal-to-noise ratio for weakly aligned films, outperforming traditional optical methods.
- SHEL correlation with UV–Vis and POM measurements confirms its reliability for alignment studies.

## Abstract

In this paper, we propose a scheme based on the spin Hall effect of light (SHEL) for characterizing aligned polymers. Poly (3-hexylthiophene) (P3HT) films were prepared via the solution shear coating method. The experimental results obtained by using SHEL indicated that the alignment of polymer chains could be enhanced by UV irradiation and was positively correlated with the irradiation time, which was consistent with the measurements of the UV–Vis spectrometer and the polarizing optical microscope (POM). Compared with other optical methods, such as POM that characterizes aligned samples using light intensity, the amplified shift in SHEL can significantly reduce technical noise and exhibit high sensitivity. Even for the weak alignment film, this method can still recognize its alignment and achieve a signal-to-noise ratio (SNR) of 30 dB. This renders SHEL a highly precise technique for studying aligned polymers, which is valuable for the development of organic electronics.