Relaxation of critical fluctuations after cessation of simple shear flow

Scattering experiments under shear of a near-critical system show a highly anisotropic static structure factor. We present small angle light scattering experiments on the relaxation of this anisotropic structure factor of a near-critical colloidal system after cessation of a simple shear flow. The structure factor is found to develop a scattering ring, which shifts to smaller wave vectors in time and increases in intensity. A theoretical explanation of this phenomenon is proposed.