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arXiv · 2308.08175

High mobility transport in isotopically-enriched $^{12}$C and $^{13}$C exfoliated graphene

Shuichi Iwakiri·Jakob Miller·Florian Lang·Jakob Prettenthaler·Takashi Taniguchi·Kenji Watanabe·Sung Sik Lee·Pascal Becker·Detlef Günther·Thomas Ihn·Klaus Ensslin
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Abstract

Graphene quantum dots are promising candidates for qubits due to weak spin-orbit and hyperfine interactions. The hyperfine interaction, controllable via isotopic purification, could be the key to further improving the coherence. Here, we use isotopically enriched graphite crystals of both $^{12}$C and $^{13}$C grown by high-pressure-high-temperature method to exfoliate graphene layers. We fabricated Hall bar devices and performed quantum transport measurements, revealing mobilities exceeding $10^{5}$$\textrm{cm}^{2}/Vs$ and a long mean free path of microns, which are as high as natural graphene. Shubnikov-de Haas oscillations, quantum Hall effect up to the filling factor of one, and Brown-Zak oscillations due to the alignment of hBN and graphene are observed thanks to the high mobility. These results constitute a material platform for physics and engineering of isotopically-enriched graphene qubits.

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Shuichi Iwakiri, Jakob Miller, Florian Lang, Jakob Prettenthaler, Takashi Taniguchi, Kenji Watanabe, Sung Sik Lee, Pascal Becker, Detlef Günther, Thomas Ihn, Klaus Ensslin. 2023-08-16. High mobility transport in isotopically-enriched $^{12}$C and $^{13}$C exfoliated graphene. https://doi.org/10.1103/physrevresearch.5.043212

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