The PolySense team has just published a new article on Sensors Journal (IF 3.84) reporting on the implementation of an innovative multi-quantum cascade laser (QCL) module for quartz-enhanced photoacoustic spectroscopy (QEPAS) sensing. The source is composed of three different QCLs coupled with a dichroitic beam combiner module that provides an overlapping collimated beam output for all three QCLs. The 3-QCL QEPAS
sensor was tested for detection of NO2, SO2, and NH3 in sequence in a laboratory environment. Detection limits of 9 ppb, 9.3 ppb, and 2.4 ppb of were reached for NO2, SO2, and NH3, well below their typical natural abundance in air.
The following link provides access to the article: