A tunable source of correlated atom beans

13 12/2013

Friday, 13 Dec. 2013, 10:30 - 11:30

Presenter: Marie Bonneau
Host: J. Schmiedmayer
Where: Seminarraum Atominstitut

I will present an experiment which enables production and characterization of macroscopic twin atomic beams. Spontaneous four wave mixing (SFWM) of matter waves is used as a source of non-classical atomic pair states, similar to the twin photon states generated through parametric down-conversion and widely used in quantum optics. In this experiment, SFWM is performed in a moving one-dimensional optical lattice, from a metastable helium BEC. The lattice modifies the dispersion relation of the atoms, so that pairs of atoms are efficiently scattered into two twin beams, whose momenta are precisely tunable. Like their photonic analog, the two atomic beams are correlated in momentum, and their population difference exhibits sub-shot noise fluctuations. These properties, and the ability to control the beams population, makes this source suitable for a variety of quantum atom optics experiments, in the limit of either high or low mode occupancy.