QCLs are promising spectroscopic sources for developing analytical instrumentation.
WMS is a sensitive spectroscopy technique for gas sensing.
A versatile QCL sensor based on dual spectroscopic techniques was developed for simultaneous measurement of multi-species.
Measurement precisions of 0.21 ppb for CO, 0.18 ppb for N2O and 5.65 ppm for H2O were achieved at the optimal averaging time of 75 s.