Bichromatic beam splitter for three-level atoms

Abstract

We investigate schemes for the clean splitting of beams of three-level atoms using two standingwave laser fields within an optical cavity. The proposed beam splitter is shown to work for atoms in the A, ladder, and V configurations. For appropriate values of Rabi frequencies and detunings, we obtain a triangular type of potential for the atomic states of interest. As well as modeling the coherent evolution of the systems, we have used quantum Monte Carlo wave-function methods to model the effects of spontaneous emission on the resulting diffraction pattern, finding significant differences between the three configurations.We also investigate the limits of the Raman-Nath approximation for our systems, using the symmetric split-operator technique to include the effects of the kinetic term in the Hamiltonian. We also present the results of calculations in which the split output beams are recombined, demonstrating the expected interference for differently prepared input beams. In comparison with two-level beam splitters using a single standing wave, we obtain a superior splitting, while, in comparison with magneto-optical beam splitters, our system possesses the worthwhile practical advantages of experimental simplicity.

Almost minimum error discrimination of N-ary weak coherent states by Jaynes-Cummings Hamiltonian dynamics

“…If w 1 < w 2 , light strongly interacts with an atom in the 1st excited state or with an atom in the 2nd excited state. Generally, coupling strengths have different values according to the level where a transition occurs 60 .…”

Atom gratings produced by large-angle atom beam splitters

“…A remarkable property of these forces (large magnitude in comparison with radiation forces, insensitivity to atomic velocity) allows for fast atomic beam deceleration [23] and for large angle deflections [24]. The triangular potential associated with a bichromatic field was predicted in [25], and scattering off this field has been observed [26] and studied for twolevel [27,26] and three level atoms [28][29][30][31]. Moreover, it has been shown [32] that atoms can be scattered with unit probability with a given change of momentum if a "counterintuitive pulse sequence" is used.…”