Gate-voltage dependence of inter dot coupling and Aharanov-Bohm oscillation in laterally coupled vertical double dot

We fabricated laterally coupled vertical double-dot devices and measured their electrical transport properties. In these devices, two dots are laterally coupled in parallel and connected to a common source, and drain contacts placed above, and below the two dots. The number of electrons in each dot and the inter-dot tunnel coupling are all tunable. The inter-dot tunnel coupling was changed between the weak and strong coupling regimes, as a function of gate voltage placed between two dots. When a magnetic field was applied parallel to the plane of the two dots and source/drain contacts, we observed oscillations of the current (Aharanov-Bohm oscillation) in the weak coupling regime (for a different device).