PT - JOURNAL ARTICLE AU - Kurotani, Yuji AU - Tanaka, Hajime TI - A novel physical mechanism of liquid flow slippage on a solid surface AID - 10.1126/sciadv.aaz0504 DP - 2020 Mar 01 TA - Science Advances PG - eaaz0504 VI - 6 IP - 13 4099 - http://advances.sciencemag.org/content/6/13/eaaz0504.short 4100 - http://advances.sciencemag.org/content/6/13/eaaz0504.full SO - Sci Adv2020 Mar 01; 6 AB - Viscous liquids often exhibit flow slippage on solid walls. The occurrence of flow slippage has a large impact on the liquid transport and the resulting energy dissipation, which are crucial for many applications. It is natural to expect that slippage takes place to reduce the dissipation. However, (i) how the density fluctuation is affected by the presence of the wall and (ii) how slippage takes place through forming a gas layer remained elusive. Here, we report possible answers to these fundamental questions: (i) Density fluctuation is intrinsically enhanced near the wall even in a quiescent state irrespective of the property of wall, and (ii) it is the density dependence of the viscosity that destabilizes the system toward gas-layer formation under shear flow. Our scenario of shear-induced gas-phase formation provides a natural physical explanation for wall slippage of liquid flow, covering the slip length ranging from a microscopic (nanometers) to macroscopic (micrometers) scale.