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arXiv · 1803.06548

Perpetual emulation threshold of PT-symmetric Hamiltonians

D. Trypogeorgos·A. Valdés-Curiel·I. B. Spielman·C. Emary
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Abstract

We describe a technique to emulate a two-level \PT-symmetric spin Hamiltonian, replete with gain and loss, using only the unitary dynamics of a larger quantum system. This we achieve by embedding the two-level system in question in a subspace of a four-level Hamiltonian. Using an \textit{amplitude recycling} scheme that couples the levels exterior to the \PT-symmetric subspace, we show that it is possible to emulate the desired behaviour of the \PT-symmetric Hamiltonian without depleting the exterior, reservoir levels. We are thus able to extend the emulation time indefinitely, despite the non-unitary \PT dynamics. We propose a realistic experimental implementation using dynamically decoupled magnetic sublevels of ultracold atoms.

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D. Trypogeorgos, A. Valdés-Curiel, I. B. Spielman, C. Emary. 2018-03-17. Perpetual emulation threshold of PT-symmetric Hamiltonians. https://doi.org/10.1088/1751-8121%2Faacc5e

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