Noemi Zakarias, Susan Minkoff, and John Zweck, Department of Mathematics and Statistics

The resonant optothermoacoustic detection (ROTADE) method relies
on the theory of optothermal spectroscopy and the mechanical and
piezoelectric properties of a quartz tuning fork. ROTADE sensors enable
detection of trace gases for air quality monitoring, industrial process
control, and medical diagnostics. To detect a trace gas, modulated laser
radiation is directed between the tines of a tuning fork. The laser source
transfers energy to the trace gas molecules, these diffuse in space and
come into contact with the surface of the tuning fork causing the surface
to heat up. The optical energy absorbed by the gas results in a periodic
thermal expansion which is converted into an electric current via the
piezoelectric effect. The purpose of this project is to develop a
theoretical model of a ROTADE sensor which we will use to calculate how
the signal strength of the sensor depends on the system parameters.