Gallium arsenide waveguides as a platform for direct mid-infrared vibrational spectroscopy

Julian Haas, Robert Stach, Claudia Kolm, Rudolf Krska, Boris Mizaikoff*

*Corresponding author for this work

Research output: Journal article (peer-reviewed)Journal article

2 Citations (Scopus)


During recent years, mid-infrared (MIR) spectroscopy has matured into a versatile and powerful sensing tool for a wide variety of analytical sensing tasks. Attenuated total reflection (ATR) techniques have gained increased interest due to their potential to perform non-destructive sensing tasks close to real time. In ATR, the essential component is the sampling interface, i.e., the ATR waveguide and its material properties interfacing the sample with the evanescent field ensuring efficient photon-molecule interaction. Gallium arsenide (GaAs) is a versatile alternative material vs. commonly used ATR waveguide materials including but not limited to silicon, zinc selenide, and diamond. GaAs-based internal reflection elements (IREs) are a new generation of semiconductor-based waveguides and are herein used for the first time in direct spectroscopic applications combined with conventional Fourier transform infrared (FT-IR) spectroscopy. Next to the characterization of the ATR waveguide, exemplary surface reactions were monitored, and trace-level analyte detection via signal amplification taking advantage of surface-enhanced infrared absorption (SEIRA) effects was demonstrated. As an example of real-world relevance, the mycotoxin aflatoxin B1 (AFB1) was used as a model analyte in food and feed safety analysis. [Figure not available: see fulltext.]

Original languageEnglish
Pages (from-to)3447-3456
Number of pages10
JournalAnalytical and Bioanalytical Chemistry
Issue number14
Publication statusPublished - 01 May 2020
Externally publishedYes


  • Evanescent field absorption
  • Gallium arsenide
  • Mid-infrared chem/biosensor
  • Self-assembled monolayers
  • Surface modification
  • Surface-enhanced infrared absorption

ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry


Dive into the research topics of 'Gallium arsenide waveguides as a platform for direct mid-infrared vibrational spectroscopy'. Together they form a unique fingerprint.

Cite this