The Infrared (IR) Lab is equipped with two Fourier Transform infrared spectrometers: Bruker VERTEX 80 and Bruker IFS 120/5 HR. The spectrometers work in the spectral range of 30 to 15,500 cm^-1 with resolution up to 0.075 cm^-1 and 0.0035 cm^-1 for the VERTEX 80 and IFS 120/5 HR, respectively.

Fourier-transform spectroscopy is used in the far-infrared or terahertz spectral region to record the emission spectra and evaluate the tuning behavior of quantum-cascade lasers at low temperature operated in a liquid-He flow cryostat or a mechanical cooler. In the far-infrared and mid-infrared region, transmission spectra can be measured at room temperature.