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Entanglement in quantum catastrophes

Clive Emary·Neill Lambert·Tobias Brandes
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Abstract

We classify entanglement singularities for various two-mode bosonic systems in terms of catastrophe theory. Employing an abstract phase-space representation, we obtain exact results in limiting cases for the entropy in cusp, butterfly, and two-dimensional catastrophes. We furthermore use numerical results to extract the scaling of the entropy with the non-linearity parameter, and discuss the role of mixing entropies in more complex systems.

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Clive Emary, Neill Lambert, Tobias Brandes. 2005-03-17. Entanglement in quantum catastrophes. https://doi.org/10.1103/physreva.71.062302

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