Multiphysics Simulation of Terahertz Pulse Induced Photoacoustic Wave

Terahertz optical imaging has been studied for many medical applications. However, due to the strong water absorption of terahertz waves, in order to obtain high-contrast imaging, it is necessary to consider reducing the water content of the sample, which is difficult in many cases. The terahertz wave is completely absorbed on the water surface, and this strong absorption can effectively generate terahertz photoacoustic waves. In this paper, we constructed the terahertz photoacoustic model in water at room temperature, observed the propagation of photoacoustic signal in water, and analyzed the results. The results show that the propagation depth of photoacoustic wave is much larger than the penetration depth of terahertz wave.