Spin readout and addressability of phosphorus-donor clusters in silicon

• Published in: Nature communications 2013-06, Vol.4 (1), p.2017-2017, Article 2017
• Main Authors: Büch, H., Mahapatra, S., Rahman, R., Morello, A., Simmons, M. Y.
• Format: Article
• Language: English
• Subjects: 639/766/119; 639/766/483/2802; 639/925/927/481; Humanities and Social Sciences; multidisciplinary; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms3017

The spin states of an electron bound to a single phosphorus donor in silicon show remarkably long coherence and relaxation times, which makes them promising building blocks for the realization of a solid-state quantum computer. Here we demonstrate, by high-fidelity (93%) electrical spin readout, that a long relaxation time T 1 of about 2 s, at B =1.2 T and T ≈100 mK, is also characteristic of electronic spin states associated with a cluster of few phosphorus donors, suggesting their suitability as hosts for spin qubits. Owing to the difference in the hyperfine coupling, electronic spin transitions of such clusters can be sufficiently distinct from those of a single phosphorus donor. Our atomistic tight-binding calculations reveal that when neighbouring qubits are hosted by a single phosphorus atom and a cluster of two phosphorus donors, the difference in their electron spin resonance frequencies allows qubit rotations with error rates ≈10 −4 . These results provide a new approach to achieving individual qubit addressability. The spin of an electron bound to a single phosphorus atom in silicon is of interest for spin-based electronics such as quantum computing. Here, Büch et al . show these spin properties are retained even for clusters of a few phosphorus atoms, providing an additional means for quantum bit addressability.