Random Multiple Scattering Enhanced Photoacoustic Gas Spectroscopy with Disordered Porous Ceramics

Light–gas interaction can be enhanced by using disordered porous materials because multiple random scattering increases light intensity near the surface of the material. Here we report signal enhancement of photoacoustic gas spectroscopy with disordered porous ceramics. The amplitude and frequency characteristics of photoacoustic signal due to gas absorption in disordered materials are modeled theoretically. Experiment with a porous Al2O3 sample demonstrates photoacoustic signal enhancement of ～4 times at 5 kHz