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Measurement of quantum weak values of photon polarization.

Centre for Quantum Computer Technology, Physics Department, The University of Queensland, Brisbane, Queensland 4072, Australia.
Physical Review Letters (Impact Factor: 7.73). 07/2005; 94(22):220405. DOI: 10.1103/PhysRevLett.94.220405
Source: PubMed

ABSTRACT We experimentally determine weak values for a single photon's polarization, obtained via a weak measurement that employs a two-photon entangling operation, and postselection. The weak values cannot be explained by a semiclassical wave theory, due to the two-photon entanglement. We observe the variation in the size of the weak value with measurement strength, obtaining an average measurement of the S1 Stokes parameter more than an order of magnitude outside of the operator's spectrum for the smallest measurement strengths.

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