Enhancing sensitivity in absorption spectroscopy using a scattering cavity

TL;DR

This paper introduces a scattering cavity method that significantly enhances the sensitivity of absorption spectroscopy by increasing optical path lengths through multiple light scattering, enabling detection of low-concentration samples.

Contribution

The study presents a novel scattering cavity approach that boosts absorption spectroscopy sensitivity by over ten times, applicable with minimal modifications to existing systems.

Findings

Over tenfold increase in sensitivity achieved

Effective detection of low-concentration solutions demonstrated

Method compatible with current absorption spectroscopy setups

Abstract

Absorption spectroscopy is widely used to detect samples with spectral specificity. Here, we propose and demonstrate a method for enhancing the sensitivity of absorption spectroscopy. Exploiting multiple light scattering generated by a boron nitride (h-BN) scattering cavity, the optical path lengths of light inside a diffusive reflective cavity are significantly increased, resulting in more than ten times enhancement of sensitivity in absorption spectroscopy. We demonstrate highly sensitive spectral measurements of low concentrations of malachite green and crystal violet aqueous solutions. Because this method only requires the addition of a scattering cavity to existing absorption spectroscopy, it is expected to enable immediate and widespread applications in various fields, from analytical chemistry to environmental sciences.