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arXiv · 2006.00723

Spin squeezing with short-range spin-exchange interactions

Michael A. Perlin·Chunlei Qu·Ana Maria Rey
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Abstract

We investigate many-body spin squeezing dynamics in an XXZ model with interactions that fall off with distance $r$ as $1/r^\alpha$ in $D=2$ and $3$ spatial dimensions. In stark contrast to the Ising model, we find a broad parameter regime where spin squeezing comparable to the infinite-range $\alpha=0$ limit is achievable even when interactions are short-ranged, $\alpha>D$. A region of "collective" behavior in which optimal squeezing grows with system size extends all the way to the $\alpha\to\infty$ limit of nearest-neighbor interactions. Our predictions, made using the discrete truncated Wigner approximation (DTWA), are testable in a variety of experimental cold atomic, molecular, and optical platforms.

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Michael A. Perlin, Chunlei Qu, Ana Maria Rey. 2020-06-01. Spin squeezing with short-range spin-exchange interactions. https://doi.org/10.1103/physrevlett.125.223401

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