Thermally-induced capillary waves

Quasi-elastic Laser Scattering (QELS) provides a versatile tool for monitoring in situ the frequency of thermally induced capillary waves at the Uquid/hquid junction [26, 27]. Unlike the previous techniques based on an absorption/fluores-cence signal arising from molecular probes at the interface, QELS is not sensitive to specific molecules but to the interfacial tension of the molecular junc-... 

Surface light scattering methods from thermally induced capillary waves at the interface [139-141] or from electric-field-induced surface waves [142, 143] have appeared. The technique is limited by the viscosities of the two phases if the viscosities are too large, then the spatial damping of the surface capillary waves is too rapid to be detected by the technique. The applicability of this method for highly viscous polymeric interfaces has not been verified yet. 

On the other hand, a liquid/liquid interface is fluctuating thermally in the time scale of tens of picoseconds, and this induces thermal capillary waves as discussed above. Thermal capillary waves at a flat liquid/liquid interface have been studied by laser light-scattering methods, and the wavelength of the capillary wave (2) has been reported to be A 102 /im [29-31], A large... 

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