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Quantum physics

Spin flips with a single proton


For the first time, spin flips of a single trapped proton in free space have been observed. This is a major step towards a million-fold improved test of matter–antimatter symmetry using a nuclear magnetic moment.

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Figure 1: Penning trap used by Ulmer et al.1 to measure proton spin flips.


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Correspondence to Rainer Blatt.

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Blatt, R. Spin flips with a single proton. Nature 475, 298–299 (2011).

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