Coherent Anti-Stokes Raman Scattering Heterodyne Interferometry

TL;DR

This paper introduces a heterodyne interferometry method for CARS signals, enhancing sensitivity and enabling molecular contrast in OCT by overlapping and interfering two generated CARS signals.

Contribution

It presents a novel interferometric technique utilizing heterodyne detection for CARS, improving sensitivity and potential applications in optical imaging.

Findings

Demonstrated interference of two CARS signals in an interferometer

Showed increased detection sensitivity through heterodyne detection

Facilitated potential use in molecular contrast OCT

Abstract

A new interferometric technique is demonstrated for measuring Coherent Anti-Stokes Raman Scattering (CARS) signals. Two forward-directed CARS signals are generated, one in each arm of an interferometer. The deterministic nature of the CARS process allows for these two signals, when spatially and temporally overlapped, to interfere with one another. Heterodyne detection can therefore be employed to increase the sensitivity in CARS signal detection. In addition, nonlinear CARS interferometry will facilitate the use of this spectroscopic technique for molecular contrast in Optical Coherence Tomography (OCT).