Standoff Detection via Single-Beam Spectral Notch Filtered Pulses

TL;DR

This paper introduces a simple single-beam CARS technique using a notch filter for remote detection of solids and explosives, eliminating the need for complex pulse-shaping equipment.

Contribution

It presents a novel, easy-to-implement single-beam CARS method employing a commercial notch filter, simplifying remote vibrational spectroscopy.

Findings

Effective detection of solids and explosives at >50 m

Elimination of pulse-shaper requirement

Successful identification of trace materials

Abstract

We demonstrate single-beam coherent anti-Stokes Raman spectroscopy (CARS), for detecting and identifying traces of solids, including minute amounts of explosives, from a standoff distance (>50 m) using intense femtosecond pulses. Until now, single-beam CARS methods relied on pulse-shapers in order to obtain vibrational spectra. Here we present a simple and easy-to-implement detection scheme, using a commercially available notch filter, that does not require the use of a pulse-shaper.