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arXiv · 1912.11373

Single-electron double quantum dots in bilayer graphene

Luca Banszerus·Samuel Möller·Eike Icking·Kenji Watanabe·Takashi Taniguchi·Christian Volk·Christoph Stampfer
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Abstract

We present transport measurements through an electrostatically defined bilayer graphene double quantum dot in the single electron regime. With the help of a back gate, two split gates and two finger gates we are able to control the number of charge carriers on two gate-defined quantum dot independently between zero and five. The high tunability of the device meets requirements to make such a device a suitable building block for spin-qubits. In the single electron regime, we determine interdot tunnel rates on the order of 2~GHz. Both, the interdot tunnel coupling, as well as the capacitive interdot coupling increase with dot occupation, leading to the transition to a single quantum dot. Finite bias magneto-spectroscopy measurements allow to resolve the excited state spectra of the first electrons in the double quantum dot; being in agreement with spin and valley conserving interdot tunneling processes.

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Luca Banszerus, Samuel Möller, Eike Icking, Kenji Watanabe, Takashi Taniguchi, Christian Volk, Christoph Stampfer. 2019-12-24. Single-electron double quantum dots in bilayer graphene. https://doi.org/10.1021/acs.nanolett.9b05295

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