Height fluctuations of a contact line: A direct measurement of the renormalized disorder correlator

摘要: We measure the center-of-mass fluctuations of height a contact line at depinning for two different systems: liquid hydrogen on rough cesium substrate and isopropanol silicon wafer grafted with silanized patches. The is subject to confining quadratic well, provided by gravity. From second cumulant fluctuations, we renormalized disorder correlator Δ(u), predicted Functional RG attain fixed point, as soon capillary length large compared Larkin set microscopic disorder. experiments are consistent asymptotic form Δ(u) RG, including linear cusp u=0. observed small deviations could be used probe underlying physical processes. third moment, well avalanche-size distributions measured predictions from RG.