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arXiv · 2106.07460

Spin squeezing from bilinear spin-spin interactions: two simple theorems

Tommaso Roscilde·Fabio Mezzacapo·Tommaso Comparin
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Abstract

We demonstrate two simple theorems about squeezing induced by bilinear spin-spin interactions that conserve spin parity -- including a vast majority of quantum spin models implemented by state-of-the-art quantum simulators. In particular we show that squeezing captures the first form of quantum correlations which are produced: 1) at equilibrium, by adiabatically turning on the spin-spin interactions starting from a factorized state aligned with an external, arbitrary field; 2) away from equilibrium, by evolving unitarily the same state with the interacting Hamiltonian.

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Tommaso Roscilde, Fabio Mezzacapo, Tommaso Comparin. 2021-06-14. Spin squeezing from bilinear spin-spin interactions: two simple theorems. https://doi.org/10.1103/physreva.104.l040601

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