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arXiv · 1509.03965

Crystallization of fractional charges in a strongly interacting quasi-helical quantum dot

F. Cavaliere·F. M. Gambetta·S. Barbarino·M. Sassetti
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Abstract

The ground-state electron density of a one-dimensional spin-orbit coupled quantum dot with a Zeeman term and strong electron interaction is studied at the fractional helical liquid points. We show that at fractional filling factors $ν=(2n+1)^{-1}$ (with $n$ a non-negative integer) the density oscillates with $N_{0}/ν$ peak. For $n\geq 1$ a number of peaks larger than the number of electrons $N_{0}$ suggests that a crystal of fractional quasi-particles with charge $νe$ (with $e$ the electron charge) occurs. The reported effect is amenable of verification via transport measurements in charged AFM-coupled dot.

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F. Cavaliere, F. M. Gambetta, S. Barbarino, M. Sassetti. 2015-09-14. Crystallization of fractional charges in a strongly interacting quasi-helical quantum dot. https://doi.org/10.1103/physrevb.92.235128

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