OBSERVATION OF DOUBLE STABLE CLOUDS OF COLD ATOMS IN MAGNETOOPTICAL TRAPS

We present the observation of double stable clouds of cold trapped ato ms in a magneto-optical trap and its explanation with a simple model b ased on radiative forces. This structure occurs for a specific misalig nment of the trapping laser beams whose Gaussian profiles introduce an extra term in the equation of motion for the trapped atom. We were ab le to obtain simple analytical expressions for the trap potential and for the separation of the clouds, and carried out a numerical calculat ion which agrees well with the experimental observations.