Enhancing sensitivity in tuning fork photoacoustic spectroscopy systems

A fast, high-sensitivity detector is required for studies of environmentally relevant gases. Photoacoustic spectroscopy (PAS), an absorption spectroscopy technique in which absorption is detected as sound, is explored as a possible solution. A tuning-fork based PAS sensor is modeled using COMSOL Multiphysics. The model combines the acoustic and piezoelectric modules and also includes viscous damping. The model is validated by comparison to experimental data. Acoustic resonator tubes have been found to enhance the signal in these systems. Here the model is applied to determine the dependence of the signal on resonator tube dimensions.