Optical quantum sensors

Q-FTIR Quanten-Fourier-Transform-Spektrometer
© Fraunhofer IPM
The Q-FTIR demonstrator combines quantum technology with classical Fourier transform infrared spectroscopy. This results in a high-performance measurement system for infrared spectroscopy with »undetected photons«.

Infrared spectroscopy without infrared detectors

The mid-infrared spectral range contains a particularly large amount of information on the composition of a spectroscopic sample. Detectors for this spectral range, however, are usually technologically complex, expensive, and often require cooling. In the visible to near-infrared spectral range, on the other hand, high-performance and cost-effective silicon detectors are available. Interference effects of correlated photon pairs enable infrared spectroscopy by detecting visible light. In our »Nonlinear Optics and Quantum Sensing« team, we are conducting research on the use of this quantum technology for performant spectroscopic analytics.

Measuring with »undetected photons«

At the heart of the technology is the correlated photon source. This is realized as a nonlinear optical crystal in which photons of a pump laser beam can »split« into two correlated photons, called signal and idler. The idler photon then lies in the infrared spectral range (for spectroscopy), the corresponding signal photon in the visible or near-infrared (for detection).

In a nonlinear interferometer, the light from two such photon sources is superimposed. Since the signal and idler photons of the two processes are not distinguishable, interference occurs for both photons. If now a sample absorbs mid-infrared idler photons from the first process, the light sources become distinguishable and the idler interference contrast decreases. Since signal and idler photons are correlated, the signal interference contrast is also reduced. It is thus possible to determine the transmission of the sample for the mid-infrared idler light solely by detecting the (visible or near-infrared) signal interference pattern. This quantum effect can be used for various measurements with »undetected photons«.

The quantum Fourier transform spectrometer

The quantum Fourier transform spectrometer Q-FTIR developed at Fraunhofer IPM enables precise spectroscopy in the mid-infrared with only near-infrared light detection. For this, extremely low optical power on the sample is sufficient – more than six orders of magnitude less infrared power than a typical Fourier transform spectrometer. The Q-FTIR is based on the same measuring principle as classical instruments and thus achieves high spectral resolution. As part of the Fraunhofer lighthouse project QUILT, a highly performant mobile demonstrator for spectroscopic analysis has been realized.

Further information

 

Lighthouse Project »QUILT«

The Lighthouse Project »QUILT« bundles the outstanding scientific expertise, technology platforms and considerable market knowledge of six Fraunhofer institutes with the scientific excellence of global leaders in quantum technology.

 

Pres / 3.1.2022

Quantum imaging: Pushing the boundaries of optics

Unearthing the possibilities of quantum technology for imaging techniques, microscopy and spectroscopy was the focus of the Fraunhofer lighthouse project QUILT. As part of QUILT Fraunhofer IPM developed a world first: the »Quantum FTIR«, which is the quantum optical equivalent to the classical Fourier transform spectrometer.

Publications »Optical quantum sensors«

Jahr
Year
Titel/Autor:in
Title/Author
Publikationstyp
Publication Type
2023 High-sensitivity quantum sensing with pump-enhanced spontaneous parametric down-conversion
Lindner, Chiara; Kunz, Jachin; Herr, Simon; Kießling, Jens; Wolf, Sebastian; Kühnemann, Frank
Zeitschriftenaufsatz
Journal Article
2023 Fourier-transform mid-IR hyperspectral imaging with undetected photons
Placke, Marlon; Lindner, Chiara; Kviatkovsky, Inna; Chrzanowski, Helen M.; Kühnemann, Frank; Ramelow, Sven
Konferenzbeitrag
Conference Paper
2023 High resolution Fourier-transform mid-infrared spectroscopy using nonlinear interferometers
Kunz, Jachin; Lindner, Chiara; Herr, Simon; Wolf, Sebastian; Kießling, Jens; Kühnemann, Frank
Konferenzbeitrag
Conference Paper
2023 Fourier-Transform Mid-Infrared Spectroscopy Using Nonlinear Interferometers
Kunz, Jachin; Lindner, Chiara; Herr, Simon; Wolf, Sebastian; Kießling, Jens; Kühnemann, Frank
Konferenzbeitrag
Conference Paper
2022 Nonlinear interferometers based on spontaneous parametric down-conversion for Fourier-transform mid-infrared spectroscopy
Lindner, Chiara
Dissertation
Doctoral Thesis
2022 Accurate, high-resolution dispersive Fourier-transform spectroscopy with undetected photons
Lindner, Chiara; Kunz, Jachin; Herr, Simon J.; Kießling, Jens; Wolf, Sebastian; Kühnemann, Frank
Zeitschriftenaufsatz
Journal Article
2021 Fourier-Transform Infrared Spectroscopy with Near-Infrared Light
Lindner, Chiara; Kunz, Jachin; Herr, Simon J.; Kießling, Jens; Wolf, Sebastian; Kühnemann, Frank
Konferenzbeitrag
Conference Paper
2021 Nonlinear interferometer for Fourier-transform mid-infrared gas spectroscopy using near-infrared detection
Lindner, Chiara; Kunz, Jachin; Herr, Simon J.; Wolf, Sebastian; Kießling, Jens; Kühnemann, Frank
Zeitschriftenaufsatz
Journal Article
2021 Nonlinear interferometers for Fourier-transform infrared spectroscopy with visible light
Lindner, Chiara; Kunz, Jachin; Wolf, Sebastian; Kießling, Jens; Kühnemann, Frank
Konferenzbeitrag
Conference Paper
2020 Nonlinear interferometers for broadband mid-infrared spectroscopy
Lindner, Chiara; Wolf, Sebastian; Kießling, Jens; Kühnemann, Frank
Konferenzbeitrag
Conference Paper
2020 Fourier transform infrared spectroscopy with visible light
Lindner, Chiara; Wolf, Sebastian; Kießling, Jens; Kühnemann, Frank
Zeitschriftenaufsatz
Journal Article
2019 Characterization of Broadband Spontaneous Parametric Down-Conversion in Periodically Poled Materials
Lindner, Chiara; Wolf, Sebastian; Kießling, Jens; Kühnemann, Frank
Konferenzbeitrag
Conference Paper
Diese Liste ist ein Auszug aus der Publikationsplattform Fraunhofer-Publica

This list has been generated from the publication platform Fraunhofer-Publica