Fano stability diagram of a symmetric triple quantum dot

The Fano factor stability diagram of a C3v symmetric triangular quantum dot is analyzed for increasing electron fillings N . At low filling, conventional Poissonian and sub-Poissonian behavior is found. At larger filling, N 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 .