Atomic ions entangled states

Here, we rq>ort related trapped-ion research at NIST on (1) the study of the dynamics of a two-level atomic system coupled to harmonic atomic motion, (2) the creation and characterization of nonclassical states of motion such as Schrodinger-cat superposition states, and (3) quantum logic for the generation of highly entangled states and for the investigation of scaling in a quantum computer. 

Atoms (ions) encapsulated into small-diameter (-1 nm) metallic carbon nanotubes may form quasi-one-dimensional atomic polariton states via strong coupling to the virtual photonic modes of the nanotube. This results in sizable amounts of the two-qubit atomic entanglement that persists with no damping for very long times. We expect this effect to stimulate relevant experimental efforts and thus to open a path to new device applications of atomically doped carbon nanotubes in quantum information technologies. 

Thus, atomically doped carbon nanotubes offer another, alternative way to generate the qubit entanglement by using quasi-ID atomic polariton states formed by the atoms (ions) located close to or encapsulated inside CNs. Here we show that small-diameter metallic nanotubes indeed result in sizable amounts of the two-qubit atomic entanglement for sufficiently long times. 

Blatt, R., Wineland, D. Entangled States of Trapped Atomic Ions. Nature 453(7198), 1008-1015 (2008)... 

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