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arXiv · 1610.08447

Fano stability diagram of a symmetric triple quantum dot

Michael Niklas·Andreas Trottmann·Andrea Donarini·Milena Grifoni
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Abstract

The Fano factor stability diagram of a C$_{3v}$ symmetric triangular quantum dot is analysed for increasing electron fillings $N$. At low filling, conventional Poissonian and sub-Poissonian behavior is found. At larger filling, $N\ge 2$, a breaking of the electron-hole symmetry is manifested in super-Poissonian noise with a peculiar bias voltage dependence of the Fano factor at Coulomb and interference blockade. An analysis of the Fano map unravels a nontrivial electron bunching mechanism arising from the presence of degenerate many-body states combined with orbital interference and Coulomb interactions. An expression for the associated dark states is provided for generic $N$.

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Michael Niklas, Andreas Trottmann, Andrea Donarini, Milena Grifoni. 2017-02-10. Fano stability diagram of a symmetric triple quantum dot. https://doi.org/10.1103/physrevb.95.115133

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