Multipartite entanglement among single spins in diamond.

3.Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart, Germany.
Science (Impact Factor: 31.48). 07/2008; 320(5881):1326-9. DOI: 10.1126/science.1157233
Source: PubMed

ABSTRACT Robust entanglement at room temperature is a necessary requirement for practical applications in quantum technology. We demonstrate the creation of bipartite- and tripartite-entangled quantum states in a small quantum register consisting of individual 13C nuclei in a diamond lattice. Individual nuclear spins are controlled via their hyperfine coupling to a single electron at a nitrogen-vacancy defect center. Quantum correlations are of high quality and persist on a millisecond time scale even at room temperature, which is adequate for sophisticated quantum operations.

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