YOUNGS DOUBLE-SLIT EXPERIMENT WITH ATOMS - A SIMPLE ATOM INTERFEROMETER

An atomic interferometer based on a Young's-type double-slit arrangement has been demonstrated. A supersonic beam of metastable helium atoms passes through a 2-mu-m-wide slit in a thin gold foil. This transversely coherent beam impinges on a second microfabricated transmission structure, consisting of two 1-mu-m-wide slits at a lateral distance of 8-mu-m. This double slit defines two possible paths on which the atoms can reach the detector slit. The good visibility of the observed fringes should make it possible to measure differential phase shifts in the interferometer of 1/3 rad in less than 10 min.