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arXiv · 1110.0727

Weak measurement of the Dirac distribution

Jeff S. Lundeen·Charles Bamber
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Abstract

Recent work [J.S. Lundeen et al. Nature, 474, 188 (2011)] directly measured the wavefunction by weakly measuring a variable followed by a normal (i.e. `strong') measurement of the complementary variable. We generalize this method to mixed states by considering the weak measurement of the product of the two observables, which, as a non-Hermitian operator, is normally unobservable. This generalized method provides mixed states an operational definition related to the operator representation proposed by Dirac. Uniquely, it can be performed `in situ', determing the quantum state without destroying it.

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Jeff S. Lundeen, Charles Bamber. 2011-12-22. Weak measurement of the Dirac distribution. https://arxiv.org/abs/1110.0727

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