Dual-comb photoacoustic spectroscopy

Jacob T. Friedlein, Esther Baumann, Kimberly A. Briggman, Gabriel M. Colacion, Fabrizio R. Giorgetta, Aaron M. Goldfain, Daniel I. Herman, Eli V. Hoenig, Jeeseong Hwang, Nathan R. Newbury, Edgar F. Perez, Christopher S. Yung (+2 others)
2020 Nature Communications  
Spectrally resolved photoacoustic imaging is promising for label-free imaging in optically scattering materials. However, this technique often requires acquisition of a separate image at each wavelength of interest. This reduces imaging speeds and causes errors if the sample changes in time between images acquired at different wavelengths. We demonstrate a solution to this problem by using dual-comb spectroscopy for photoacoustic measurements. This approach enables a photoacoustic measurement
more » ... ustic measurement at thousands of wavelengths simultaneously. In this technique, two optical-frequency combs are interfered on a sample and the resulting pressure wave is measured with an ultrasound transducer. This acoustic signal is processed in the frequency-domain to obtain an optical absorption spectrum. For a proof-of-concept demonstration, we measure photoacoustic signals from polymer films. The absorption spectra obtained from these measurements agree with those measured using a spectrophotometer. Improving the signal-to-noise ratio of the dual-comb photoacoustic spectrometer could enable high-speed spectrally resolved photoacoustic imaging.
doi:10.1038/s41467-020-16917-y pmid:32561738 fatcat:qjdun2vxjvbjvlad4bhvt5cmaa