A scheme is proposed to deterministically generate four-dimensional entangled states for two distant atoms trapped in two separate cavities via adiabatic passage by one step. An optimal expression of time-dependent Rabi frequencies is selected through numerical simulation. Numerical simulation also shows that the excited probabilities of the atoms, the cavity modes and the fiber modes are very low during adiabatic passage, and the scheme is insensitive to the fluctuation of experimental parameters. The four-dimensional entanglement may be generated with high fidelity with current experimental technology.
The generation of entanglement between two identical coupled cavities, each containing a single three-level atom, is studied when the cavities exchange two coherent photons and are in the
N=2,4 manifolds, where
N represents the maximum number of photons possible in either cavity. The atom-photon state of each cavity is described by a qutrit for
N=2 and a five-dimensional qudit for
N=4. However, the conservation of the total value of
N for the interacting two-cavity system limits the total number of states to only 4 states for
N=2 and 8 states for
N=4, rather than the usual 9 for two qutrits and 25 for two five-dimensional qudits. In the
N=2 manifold, two-qutrit states dynamically generate four maximally entangled Bell states from initially unentangled states. In the
N=4 manifold, two-qudit states dynamically generate maximally entangled states involving three or four states. The generation of these maximally entangled states occurs rather rapidly for large hopping strengths. The cavities function as a storage of periodically generated maximally entangled states.