Fourier-Transform Infrared Spectroscopy with Undetected Photons

Chiara Lindner, Fraunhofer IPM

E-Mail: Chiara.Lindner@ipm.fraunhofer.de

Abstract:

Fourier-Transform infrared spectroscopy (FTIR) is a widely used method for studying and identifying chemical compounds, relying on interference effects to determine infrared spectral information. Despite the great advances of FTIR technology, infrared detectors remain a limiting factor due to their slower speeds, higher costs and greater noise compared to visible light detectors.

In my research, I investigate quantum interference effects of correlated photons for high-resolution infrared spectroscopy using visible light detection. Nonlinear interferometers based on spontaneous parametric down-conversion (SPDC) allow for measuring a sample’s infrared transmission by detecting only visible light.

While transforming this quantum optical experiment into a practical spectrometer poses challenges, I have found that the spectral information can be extracted similarly to classical Fourier-transform spectroscopy. This work achieves broadband infrared spectroscopy with high spectral resolution and highlights fundamental relationships between indistinguishability, coherence, and spectral composition.

Short CV:

Chiara Lindner: "I   am a researcher specializing in applied quantum optics, infrared spectroscopy, nonlinear optics and photonics. I completed my undergraduate studies in physics at the University of Freiburg in 2017 and received my PhD in 2022. Since 2018, I have been working at the Fraunhofer-Institute for Physical Measurement Techniques IPM within the Photonic Systems department.

My research on the interference effects of correlated photons and their applications to infrared spectroscopy has been recognized with several awards, including the Quantum Futur Award (BMBF), the Hugo-Geiger-Preis (FhG, State of Bavaria), and the For Women in Science Germany Award (L'Oréal-UNESCO)."