Infrared Spectroscopy with Visible Light

TL;DR

This paper introduces a novel IR spectroscopy method using visible light components, leveraging nonlinear interference of photons via SPDC to analyze materials in the IR range with potentially lower cost and better performance.

Contribution

The authors develop a new spectroscopy technique that measures IR spectral properties through visible light components using nonlinear interference, enabling cost-effective and efficient IR analysis.

Findings

Allows IR spectral measurements with visible light components

Uses nonlinear interference of photons via SPDC

Potentially reduces cost and improves performance of IR spectroscopy

Abstract

Spectral measurements in the infrared (IR) optical range provide unique fingerprints of materials which are useful for material analysis, environmental sensing, and health diagnostics. Current IR spectroscopy techniques require the use of optical equipment suited for operation in the IR range, which faces challenges of inferior performance and high cost. Here we develop a spectroscopy technique, which allows spectral measurements in the IR range using visible spectral range components. The technique is based on nonlinear interference of infrared and visible photons, produced via Spontaneous Parametric Down Conversion (SPDC). The intensity interference pattern for a visible photon depends on the phase of an IR photon, which travels through the media. This allows determining properties of the media in the IR range from the measurements of visible photons. The technique can substitute and/or complement conventional IR spectroscopy techniques, as it uses well-developed optical components for the visible range.