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Resonant Tunneling and Persistent Current of a Non-interacting and Weakly Interacting One-dimensional Electron Gas

I. V. Krive·P. Sandström
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Abstract

The persistent current for a one-dimensional ring with two tunnel barriers is considered in the limit of weakly interacting electrons. In addition to a small off-resonance current, there are two kinds of resonant behavior; (i) a current independent of the barrier transparency (true resonance) and (ii) a current analogous to the one for a ring with only a single barrier (``semi''-resonance). For a given barrier transparency one or the other type of resonant behavior is realized depending on a geometric factor (ratio of interbarrier distance to ring circumference) and on the strength of the electron-electron interaction. It is shown that a repulsive interaction favours the``semi''-resonance behavior. For a small barrier transparency the ``semi''-resonance peaks are easily washed out by temperature whereas the true resonance peaks survive.

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I. V. Krive, P. Sandström. 1997-04-17. Resonant Tunneling and Persistent Current of a Non-interacting and Weakly Interacting One-dimensional Electron Gas. https://arxiv.org/abs/cond-mat/9704151

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