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arXiv · 1803.02923

Spin and Valley States in Gate-defined Bilayer Graphene Quantum Dots

Marius Eich·František Herman·Riccardo Pisoni·Hiske Overweg·Annika Kurzmann·Yongjin Lee·Peter Rickhaus·Kenji Watanabe·Takashi Taniguchi·Manfred Sigrist·Thomas Ihn·Klaus Ensslin
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Abstract

In bilayer graphene, electrostatic confinement can be realized by a suitable design of top and back gate electrodes. We measure electronic transport through a bilayer graphene quantum dot, which is laterally confined by gapped regions and connected to the leads via p-n junctions. Single electron and hole occupancy is realized and charge carriers $n = 1, 2,\dots 50$ can be filled successively into the quantum system with charging energies exceeding $10 \ \mathrm{meV}$. For the lowest quantum states, we can clearly observe valley and Zeeman splittings with a spin g-factor of $g_{s}\approx 2$. In the low field-limit, the valley splitting depends linearly on the perpendicular magnetic field and is in qualitative agreement with calculations.

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Marius Eich, František Herman, Riccardo Pisoni, Hiske Overweg, Annika Kurzmann, Yongjin Lee, Peter Rickhaus, Kenji Watanabe, Takashi Taniguchi, Manfred Sigrist, Thomas Ihn, Klaus Ensslin. 2018-08-07. Spin and Valley States in Gate-defined Bilayer Graphene Quantum Dots. https://doi.org/10.1103/physrevx.8.031023

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