State permutations from manipulation of near level-crossings
arXiv:quant-ph/0204136 · doi:10.1103/PhysRevA.68.032307
Abstract
We discuss some systematic methods for implementing state manipulations in systems formally similar to chains of a few spins with nearest-neighbor interactions, arranged such that there are strong and weak scales of coupling links. States are permuted by means of bias potentials applied to a few selected sites. This generic structure is then related to an atoms-in-a-cavity model that has been proposed in the literature as a way of achieving a decoherence free subspace. A new method using adiabatically varying laser detuning to implement a CNOT gate in this model is proposed.
6 pages, 5 figures. Substantial revision and extension of the introduction and the atoms-in-a-cavity sections