Lithium atom interferometer using laser diffraction : description and   experiments
  We have built and operated an atom interferometer of the Mach-Zehnder type. The atomic wave is a supersonic beam of lithium seeded in argon and the mirrors and beam-splitters for the atomic wave are based on elastic Bragg diffraction on laser standing waves at 671 nm. We give here a detailed description of our experimental setup and of the procedures used to align its components. We then present experimental signals, exhibiting atomic interference effects with a very high visibility, up to 84.5 %. We describe a series of experiments testing the sensitivity of the fringe visibility to the main alignment defects and to the magnetic field gradient. 
Alain Miffre (LCAR), Marion Jacquey (LCAR), Matthias B\"uchner (LCAR),   G\'erard Trenec (LCAR), Jacques Vigue (LCAR)