Flow dynamics of sheared liquids explored by inelastic neutron scattering

We have applied high resolution neutron spectroscopy to elucidate the dynam ics of sheared liquids. At room temperature, the macroscopic flow of the lu bricant yields a peak of the scattered intensity at roughly half the veloci ty of the driving disk demonstrating a nonclassical flow, whereas at higher temperature the expected linear velocity profile establishes. The data als o give information on a modification of local diffusion modes for a liquid in a shear field. (C) 1999 American Institute of Physics. [S0003-6951(99)05 323-1].