Generalized liquid drop interferometry and its implications

We investigate photomolecular-induced evaporation of water droplets on both smooth and rough substrates in a spectral region of minimal absorption, uncovering a pronounced sensitivity to light polarization and substrate scattering. Precisely measuring the resulting enhancement in evaporation rate is difficult on highly reflective smooth surfaces and on rough surfaces alike, where optical interference and loss of contrast obscure the signal. To overcome these limitations, we have developed a versatile interferometric method that tracks localized intensity changes to recover clear sinusoidal fringe patterns even in low-contrast settings. Moreover, our results show that light scattering from rough substrates can significantly boost photomolecular evaporation. Together, these advances not only deepen our understanding of light-driven phase transitions at interfaces but also open new possibilities for precise, photothermal control of interfacial dynamics.