Fig. 4
From: Photothermal Effect of Modulating Laser Irradiation on the Thermal Diffusivity of Al2O3 Nanofluids
The real (in-phase) part of PE signal vs relative cavity length for water at different frequencies: a 7 Hz, b 20 Hz, c 50 H, and d 100 Hz, thermal diffusivity of water (αw,=0.00145 cm2.s−1)