Abstract

Three 0.2 micron period diffraction gratings were used to realize an interferometer for atoms and molecules¹ that passes the interfering components of the de-Broglie wave on opposite sides of a stretched metal foil positioned between two side plates. The foil was 10 cm long and 10 µm thick, and a gas sample of density ~2 × 10¹³ atoms/cm³ could be introduced on one side of the foil only. With this septum in place, we have observed atomic (molecular) fringes with 30% (7%) contrast and an interference amplitude of more than 3500 (50) counts/ s. We can determine the phase of the interference pattern with a precision of 5(200) mrad in one minute.

© 1994 IEEE