Absorptive masks of light: A useful tool for spatial probing in atom optics

We demonstrate periodic localization of neutral atoms of better than 65 nm behind amplitude, i.e., absorptive masks made of light. With these masks, p roduced by a standing on resonant light wave, it is possible to-create and to probe spatially well-defined atomic distributions. Applications of such absorptive masks range from atom lithography to fundamental atom optical ex periments. As two examples we show how to use these gratings as a tool to m easure the evolution of an atomic wave held behind a static Bragg crystal a nd its dependence on the incidence angle of the atomic beam and how to demo nstrate the frequency shift of atoms diffracted at a modulated Bragg crysta l in a beating experiment. (C) 1998 American Vacuum Society. [S0734-211X(98 )18706-1].