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arXiv · 1205.1238

Sequential measurement of conjugate variables as an alternative quantum state tomography

Antonio Di Lorenzo
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Abstract

It is shown how it is possible to reconstruct the initial state of a one-dimensional system by measuring sequentially two conjugate variables. The procedure relies on the quasi-characteristic function, the Fourier-transform of the Wigner quasi-probability. The proper characteristic function obtained by Fourier-transforming the experimentally accessible joint probability of observing "position" then "momentum" (or vice versa) can be expressed as a product of the quasi-characteristic function of the two detectors and that, unknown, of the quantum system. This allows state reconstruction through the sequence: data collection, Fourier-transform, algebraic operation, inverse Fourier-transform. The strength of the measurement should be intermediate for the procedure to work.

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Antonio Di Lorenzo. 2013-01-04. Sequential measurement of conjugate variables as an alternative quantum state tomography. https://doi.org/10.1103/physrevlett.110.010404

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