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arXiv · 1111.5910

How weak values emerge in joint measurements on cloned quantum systems

Holger F. Hofmann
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Abstract

A statistical analysis of optimal universal cloning shows that it is possible to identify an ideal (but non-positive) copying process that faithfully maps all properties of the original Hilbert space onto two separate quantum systems. The joint probabilities for non-commuting measurements on separate clones then correspond to the real parts of the complex joint probabilities observed in weak measurements on a single system, where the measurements on the two clones replace the corresponding sequence of weak measurement and post-selection. The imaginary parts of weak measurement statics can be obtained by replacing the cloning process with a partial swap operation. A controlled-swap operation combines both processes, making the complete weak measurement statistics accessible as a well-defined contribution to the joint probabilities of fully resolved projective measurements on the two output systems.

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Holger F. Hofmann. 2011-11-25. How weak values emerge in joint measurements on cloned quantum systems. https://doi.org/10.1103/physrevlett.109.020408

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