Quartz-enhanced photoacoustic spectroscopy

A new approach to detecting a weak photoacoustic signal in a gas medium is described. Instead of a gas-filled resonant acoustic cavity, the sound energy is accumulated in a high-Q crystal element. Feasibility experiments utilizing a quartz-watch tuning fork demonstrate a sensitivity of 1.2 X 10(-7) cm(-1) W/rootHz. Potential further developments and applications of this technique are discussed. (C) 2002 Optical Society of America.