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Single-atom density of states of an optical lattice

C. Hooley·J. Quintanilla
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Abstract

We consider a single atom in an optical lattice, subject to a harmonic trapping potential. The problem is treated in the tight-binding approximation, with an extra parameter κdenoting the strength of the harmonic trap. It is shown that the κ\to 0 limit of this problem is singular, in the sense that the density of states for a very shallow trap (κ\to 0) is {\it qualitatively different} from that of a translationally invariant lattice (κ= 0). The physics of this difference is discussed, and densities of states and wave functions are exhibited and explained.

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C. Hooley, J. Quintanilla. 2004-05-14. Single-atom density of states of an optical lattice. https://doi.org/10.1103/physrevlett.93.080404

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