Negative differential conductance in metallic double quantum dot structures

We show that negative differential conductance (NDC) can be observed in metallic quantum dot structures. For a simple model at zero temperature we have derived an analytical expression for the current-voltage characteristics and a condition for observing NDC. For devices with gates at finite temperatures, using the Monte Carlo method we have suggested diagrams describing a correlation between the gate capacitance or temperature and the inter-dot coupling in producing (or removing) NDC.