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arXiv · 1110.5803

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

Stefan Fringes·Christian Volk·Bernat Terrés·Jan Dauber·Stephan Engels·Stefan Trellenkamp·Christoph Stampfer
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Abstract

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.

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Stefan Fringes, Christian Volk, Bernat Terrés, Jan Dauber, Stephan Engels, Stefan Trellenkamp, Christoph Stampfer. 2011-10-26. Tunable capacitive inter-dot coupling in a bilayer graphene double quantum dot. https://doi.org/10.1002/pssc.201100340

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