Infrared Sensor Technology and Spectroscopy

Optical chemical sensor technology in the mid-infrared (MIR) spectral range (3-20 µm) is gaining importance in process monitoring, environmental analysis, and the biomedical field due to the increasing demand for versatile and robust sensor technology with inherent molecular specificity. Interfacing IR transducers with continuous measurement or surveillance situations becomes increasingly feasible with the advent of appropriate waveguide technology (e.g., MIR transparent optical fibers, planar semiconductor waveguides and resonators, etc.), innovative surface coatings (e.g., functionalized polymers, diamond-like carbon, etc.), and the availability of advanced light sources such as e.g., room-temperature operated tunable quantum cascade lasers (QCLs) next to conventional FT-IR spectrometers.

Our fundamental research interests focus on the development of innovative infrared sensing concepts with particular emphasis on system miniaturization/integration, concepts for increased sensitivity in liquid and gas phase sensing applications, and medical applications of IR diagnostics. Recently, we have been extending our efforts into the far-infrared/terahertz spectral regime (THz, 20-300 µm) with main emphasis on nearfield imaging techniques, and integrated sensing platforms for the label-free detection of biomolecular interactions (e.g., DNA hybridization).

Furthermore, we develop deep-sea deployable MIR sensing techniques enabling molecularly selective detection at extreme environmental conditions (e.g., gas hydrates, diamandoids, marine sediments, etc.). These efforts are complemented by the development of novel concepts in multivariate data analysis for autonomous sensor operation and data mining.

Current Projects

  • Evanescent field sensors based on quantum cascade laser
  • Trace gas analysis with hollow waveguides
  • Planar MIR semiconductor waveguides and resonators
  • Deep sea MIR sensor technology and spectroscopy
  • MIR sensors and spectroelectrochemistry with DLC-coated waveguides
  • Integrated nearfield THz technology
  • Virtual MIR sensors - Modeling and simulation
  • New concepts in multivariate data analysis