CALCIUM-ATOM INTERFEROMETER COMPRISED OF 4 COPROPAGATING TRAVELING LASER-BEAMS

Four laser beams traveling in the same direction that split and reflect a thermal calcium atomic beam compose an atomic interferometer like the Mach-Zehnder optical interferometer. The interference performance of the atomic interferometer was examined by changing the phase of the induced dipole moment in the atomic wave due to the laser beams, or the phase of atomic ''wavepacket'' in an atomic trajectory due to the ac Stark effect. An interference signal with a visibility of more than 15% was obtained. This interferometer will be useful in the detection of weak signals that require a long integration time, since it is less sensitive to the fluctuation of the laser frequency compared with the optical Ramsey atomic interferometer. © 1995 The American Physical Society.