Entangled light pulses from single cold atoms

Abstract

The coherent interaction between a laser-driven single trapped atom and an optical high-finesse resonator allows to produce entangled multi-photon light pulses on demand. The mechanism is based on the mechanical effect of light. The degree of entanglement can be controlled through the parameters of the laser excitation. Experimental realization of the scheme is within reach of current technology. A variation of the technique allows for controlled generation of entangled subsequent pulses, with the atomic motion serving as intermediate memory of the quantum state.

4 pages, 3 figures, revised version (new scheme for generation of subsequent pairs of entangled pulses included). Accepted for publication in Phys. Rev. Lett