7. Conclusion and Outlook

The primary objective of this study was to explore the fundamental mechanisms of interaction between a light wave and liquids that enable these liquids to be set in motion, either temporarily or permanently. The second objective was to determine to what extent these mechanisms can be applied for versatile, contactless actuation of fluids using light within a framework that could be described as an “optical lab-on-a-chip ." Radiation pressure and thermocapillary coupling act on interfaces by inducing normal or tangential stress. Diffusion forces in suspensions and thermogravity coupling are volume-dependent. Radiation pressure induces only transient flows, whereas all other mechanisms produce steady-state flows. Consequently, light offers a diverse range of interaction mechanisms that opens the door to numerous applications, ranging from adaptive optics to small-scale rheology (radiation...