Photothermal spectroscopy

Detection of trace gases and detection of residual absorbtion

Highly sensitive laser-based spectroscopy methods are primarily used for analytical tasks when it comes to detecting low trace gas concentrations or residual absorption in optical materials. Photothermal common-path interferometry (PCI) uses the secondary effect of the refractive index change resulting from the absorption-induced heating of a material. The absorbed radiation of a powerful pump laser in the material produces a change in the refractive index (»thermal lens«). A second, weak probe laser crosses the beam of the pump laser. The thermal lens causes a modification in the wavefront of the probe laser. Using a lock-in method, this can be measured very sensitively and the strength of the absorption can be determined.

© Fraunhofer IPM
Schematic structure of the PCI spectrometer

Applications »Photothermal spectroscopy«

 

Quality inspection of high-performance laser optics

Among other applications, Fraunhofer IPM uses photothermal spectroscopy to detect residual absorption in high-performance laser optics.

Spectroscopic breath analysis

Spectroscopic examination of breath provides insights into the body in a non-invasive way.

Publications »Photothermal Spectroscopy«

Jahr
Year
Titel/Autor:in
Title/Author
Publikationstyp
Publication Type
2023 Breath-Resolved Monitoring of Metabolic Trace Gases with Photothermal Spectroscopy
Wolf, Sebastian; Lindner, Chiara; Trendle, Tobias; Kießling, Jens; Wöllenstein, Jürgen; Kühnemann, Frank
Konferenzbeitrag
Conference Paper
2023 Time-resolved photothermal breath analysis
Wolf, Sebastian; Lindner, Chiara; Trendle, Tobias; Kießling, Jens; Kühnemann, Frank
Konferenzbeitrag
Conference Paper
2022 Verfahren und Sensor zum photothermischen Bestimmen einer Absorption einer elektromagnetischen Anregungsstrahlung in einer Probe
Kießling, Jens; Kühnemann, Frank; Trendle, Tobias; Wolf, Sebastian
Patent
2021 Entwicklung von Faraday-Rotatoren mit stark verbesserten Eigenschaften auf der Grundlage von Kalium-Terbium-Fluorid (KTb3F10) und anderen innovativen Materialien (IsoNova). Schlussbericht
Kühnemann, Frank; Trendle, Tobias
Bericht
Report
2020 Photothermal Common-Path Interferometry for Trace Gas Detection
Wolf, Sebastian; Trendle, Tobias; Catalan, Norman; Kießling, Jens; Wöllenstein, Jürgen; Kühnemann, Frank
Vortrag
Presentation
2018 VIS-to-NIR absorption spectroscopy of magneto-optical materials for high-power laser applications
Trendle, Tobias; Kießling, Jens; Kunz, Jachin; Kühnemann, Frank
Poster
2017 Measuring residual absorption in highly transparent optical materials using tunable sources. On calibration, spectroscopy and cross-validation
Kühnemann, Frank; Leidinger, Markus; Kießling, Jens; Breunig, Ingo; Fieberg, Stephan; Waasem, Niklas; Buse, Karsten
Poster
Diese Liste ist ein Auszug aus der Publikationsplattform Fraunhofer-Publica

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