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arXiv · 1311.0978

Strongly Coupled Diamond Spin Qubits by Molecular Nitrogen Implantation

Takashi Yamamoto·Christoph Müller·Liam P. McGuinness·Tokuyuki Teraji·Boris Naydenov·Shinobu Onoda·Takeshi Ohshima·Jörg Wrachtrup·Fedor Jelezko·Junichi Isoya
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Abstract

Ionized nitrogen molecules ($^{15}$N$_{2}^+$) are used as efficient point sources for creating NV$^-$ pairs in diamond with nanoscale spatial separation and up to 55 kHz magnetic coupling strength. Co-implantation of $^{12}$C$^+$ increased the yield of pairs, and a $^{13}$C-depleted diamond allowed 0.65 ms coherence times to be obtained. Further coupling to a third dark spin provided a strongly coupled three spin register. These results mark an important step towards realization of multi-qubit systems and scalable NV$^-$ quantum registers.

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Takashi Yamamoto, Christoph Müller, Liam P. McGuinness, Tokuyuki Teraji, Boris Naydenov, Shinobu Onoda, Takeshi Ohshima, Jörg Wrachtrup, Fedor Jelezko, Junichi Isoya. 2013-11-05. Strongly Coupled Diamond Spin Qubits by Molecular Nitrogen Implantation. https://doi.org/10.1103/physrevb.88.201201

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