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Dynamic response of interacting one-dimensional fermions in the harmonic atom trap: Phase response and the inhomogeneous mobility

W. Wonneberger
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Abstract

The problem of the Kohn mode in bosonized theories of one-dimensional interacting fermions in the harmonic trap is investigated and a suitable modification of the interaction is proposed which preserves the Kohn mode. The modified theory is used to calculate exactly the inhomogeneous linear mobility at position z in response to a spatial force pulse at another position. It is found the inhomogeneous particle mobility exhibits resonances not only at the trap frequency but also at multiples of a new renormalized collective mode frequency which depends on the strength of the interaction. In contrast, the local response obtained by averaging over the pulse position remains that of the non-interacting system.

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W. Wonneberger. 2006-08-22. Dynamic response of interacting one-dimensional fermions in the harmonic atom trap: Phase response and the inhomogeneous mobility. https://doi.org/10.1016/j.physleta.2006.03.062

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