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arXiv · 1904.06246

Minimal energy cost of entanglement extraction

Lucas Hackl·Robert H. Jonsson
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Abstract

We compute the minimal energy cost for extracting entanglement from the ground state of a bosonic or fermionic quadratic system. Specifically, we find the minimal energy increase $\Delta E_{\mathrm{min}}$ in the system resulting from replacing an entangled pair of modes, sharing entanglement entropy $\Delta S$, by a product state, and we show how to construct modes achieving this minimal energy cost. Thus, we obtain a protocol independent lower bound on the extraction of pure state entanglement from quadratic systems. Due to their generality, our results apply to a large range of physical systems, as we discuss with examples.

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Lucas Hackl, Robert H. Jonsson. 2019-04-12. Minimal energy cost of entanglement extraction. https://doi.org/10.22331/q-2019-07-15-165

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