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arXiv · 1104.3107

Measurement induced chaos with entangled states

T. Kiss·S. Vymětal·L. D. Tóth·A. Gábris·I. Jex·G. Alber
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Abstract

The dynamics of an ensemble of identically prepared two-qubit systems is investigated which is subjected to the iteratively applied measurements and conditional selection of a typical entanglement purification protocol. It is shown that the resulting measurement-induced non-linear dynamics of the two-qubit state exhibits strong sensitivity to initial conditions and also true chaos. For a special class of initially prepared two-qubit states two types of islands characterize the asymptotic limit. They correspond to a separable and a maximally entangled two-qubit state, respectively, and their boundaries form fractal-like structures. In the presence of incoherent noise an additional stable asymptotic cycle appears.

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T. Kiss, S. Vymětal, L. D. Tóth, A. Gábris, I. Jex, G. Alber. 2011-07-11. Measurement induced chaos with entangled states. https://doi.org/10.1103/physrevlett.107.100501

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