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arXiv · 1505.02057

$^{29}$Si nuclear spins as a resource for donor spin qubits in silicon

Gary Wolfowicz·Pierre-Andre Mortemousque·Roland Guichard·Stephanie Simmons·Mike L. W. Thewalt·Kohei M. Itoh·John J. L. Morton
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Abstract

Nuclear spin registers in the vicinity of electron spins in solid state systems offer a powerful resource to address the challenge of scalability in quantum architectures. We investigate here the properties of $^{29}$Si nuclear spins surrounding donor atoms in silicon, and consider the use of such spins, combined with the donor nuclear spin, as a quantum register coupled to the donor electron spin. We find the coherence of the nearby $^{29}$Si nuclear spins is effectively protected by the presence of the donor electron spin, leading to coherence times in the second timescale - over two orders of magnitude greater than the coherence times in bulk silicon. We theoretically investigate the use of such a register for quantum error correction, including methods to protect nuclear spins from the ionisation/neutralisation of the donor, which is necessary for the re-initialisation of the ancillae qubits. This provides a route for multi-round quantum error correction using donors in silicon.

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Gary Wolfowicz, Pierre-Andre Mortemousque, Roland Guichard, Stephanie Simmons, Mike L. W. Thewalt, Kohei M. Itoh, John J. L. Morton. 2015-05-08. $^{29}$Si nuclear spins as a resource for donor spin qubits in silicon. https://doi.org/10.1088/1367-2630%2F18%2F2%2F023021

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