Thermal calcium atom interferometer comprised of three copropagating traveling laser beams

Jeremiah Birrell, Dan Christensen, Christopher Erickson +3 more

Atsuo Morinaga, Yasushi Ohuchi, Masato Nakamura +1 more

Atsuo Morinaga, T. Aoki

Shinya Yanagimachi, Y. Omi, Atsuo Morinaga

An atom interferometer comprised of four copropagating traveling laser beams has been developed using a thermal calcium atomic beam and the performance of the interference fringes was investigated experimentally. The interference fringes with a visibility of 0.2 were observed at an excitation power of 0.6 mW. The signal-to-noise ratio was about 100 at an integration time of 5 ms. The equations for the interference signal were derived from the evolution matrices of spinors and the visibility was calculated in consideration of the divergent thermal atomic beam. The experimental results were described well by the present calculation.

Martin Weitz, Tobias Heupel, Theodor W. Hänsch

Atsuo Morinaga, Yasushi Ohuchi

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.