%0 Journal Article %T Brownian diffusion of a partially wetted colloid %+ Laboratoire Charles Coulomb (L2C) %+ Laboratoire de Physique de la Matiere Molle et de la Modélisation Electromagnétique [Tunis] (LP3ME) %A Boniello, Giuseppe %A Blanc, Christophe %A Fedorenko, Denys %A Medfai, Mayssa %A Ben Mbarek, Nadia %A In, Martin %A Gross, Michel %A Stocco, Antonio %A Nobili, Maurizio %< avec comité de lecture %Z L2C:15-156 %@ 1476-1122 %J Nature Materials %I Nature Publishing Group %V 14 %N 9 %P 908 %8 2015-09 %D 2015 %R 10.1038/NMAT4348 %K colloids %K interface tension %K Brownian %K interfaces %Z Physics [physics]/Condensed Matter [cond-mat]/Soft Condensed Matter [cond-mat.soft]Journal articles %X The dynamics of colloidal particles at interfaces between two fluids plays a central role in microrheology, encapsulation, emulsification, biofilm formation, water remediation and the interface-driven assembly of materials. Common intuition corroborated by hydrodynamic theories, suggests that such dynamics is governed by a viscous force lower than that observed in the more viscous fluid. Here, we show experimentally that a particle straddling an air/water interface feels a large viscous drag that is unexpectedly larger than that measured in the bulk. We suggest that such a result arises from thermally activated fluctuations of the interface at the solid/air/liquid triple line and their coupling to the particle drag through the fluctuation–dissipation theorem. Our findings should inform approaches for improved control of the kinetically driven assembly of anisotropic particles with a large triple-line-length/particle-size ratio, and help to understand the formation and structure of such arrested materials. %G English %L hal-01202128 %U https://hal.science/hal-01202128 %~ CNRS %~ L2C %~ MIPS %~ UNIV-MONTPELLIER %~ ANR %~ UM-2015-2021