Tunable capacitive inter‐dot coupling in a bilayer graphene double quantum dot

We report on a double quantum dot which is formed in a width-modulated etched bilayer graphene nanoribbon. A number of lateral graphene gates enable us to tune the quantum dot energy levels and the tunneling barriers of the device over a wide energy range. Charge stability diagrams and in particular individual triple point pairs allow to study the tunable capacitive inter-dot coupling energy as well as the spectrum of the electronic excited states on a number of individual triple points. We extract a mutual capacitive inter-dot coupling in the range of 2–6 meV and an inter-dot tunnel coupling on the order of 1.5 µeV. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)