Conductance suppression due to correlated electron transport in coupled double quantum dots

The electrostatic interaction between two capacitively coupled metal double -dots is studied at low temperatures. Experiments show that when the Coulom b blockade is lifted by applying appropriate gate biases to both double-dot s, the conductance through each double-dot becomes significantly lower than when only one double-dot is conducting. A master equation is derived for t he system and the results obtained agree well with the experimental data. T he model suggests that the conductance lowering in each double-dot is cause d by a single-electron tunneling in the other double-dot. Here, each double -dot responds to the instantaneous, rather than average, potentials on the other double-dot. This leads to correlated electron motion within the syste m, where the position of a single electron in one double-dot controls the t unneling rate through the other double-dot. [S0163-1829(99)16347-1].