Thin liquid layers in shear: non-Newtonian effects

When shear flow is generated in molecularly thin liquid films of simple liquids confined between two parallel plates, the effective viscosity of the liquid increases by many orders of magnitude compared to its bulk value. Non-Newtonian effects such as shear thinning with a universal power law exponent of 2 3 are observed in experiments and computer simulations. We present a simple model of these phenomena based on shear melting of solid-like layers induced by the strong coupling with the crystalline walls.