Single trapped ion

D. Leibfried, R. Blatt, C. Monroe, D. Wineland, Quantum dynamics of single trapped ions. 

FIGURE 11.2 Calculated Doppler speetrum of a dipole-forbidden transition of a single trapped ion oscillating at frequencies co/ln = 0.7 MHz and ajlii = 1 MHz and cooled down to the Lamb-Dicke regime sueh that the Lamb-Dieke parameters are 0.1 in both directions (the laser wavevector has the same projeetion along the coordinates axes and O ). (Figure courtesy of Caroline Champenois, PIIM, Marseille.)... 

Bergquist, J.C. Itano, W.M. Wineland, D.J. RecoUless optical absorption and Doppler side bands of a single trapped ion. Phys. Rev. A 1987, 36, 428-430. 

For a single trapped ion, its trajectory is a superposition of a fast oscillating motion (micromotion) with frequency Q. and a slow (secular) motion that can enclose a large area in the trap. The amplitude of the micromotion is proportional ioq fq< 1. From simulations it is known that when many ions are to be stored in the trap, a small q... 

With resonant and non-resonant laser interaction we can in principle perform any arbitrary 1-bit quantum gate on atoms. Atomic qubits are technologically feasible and have already been realized experimentally for example in the context of single trapped ions (Bollinger et al. 1991). The basics of this technology will be discussed in Section 6.4.5. 

A physical system to store the qubits reliably. Quantum information stored in trapped ions can persist for a very long time. Experiments with single trapped ions have shown that quantum superpositions stored in hyperfine-ground state sublevels can survive for several minutes (Bollinger et al. 1991). 

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