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arXiv · 1903.11108

Probing the Lee-Yang zeros of a spin bath by correlation functions and entanglement of two spins

A. R. Kuzmak·V. M. Tkachuk
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Abstract

We study the Lee-Yang zeros of the ferromagnetic Ising bath via the interaction with the two probe spins. Similarly as in paper [Bo-Bo Wei, Ren-Bao Liu, Phys. Rev. Lett. 109, 185701 (2012)] the problem of detecting the zeros is reduced to the exploration of time evolution of probe spins. As a result, the relation between the Lee-Yang zeros of the bath and correlation functions of the probe system is obtained. Also we obtain relation between the Lee-Yang zeros and values of the entanglement of probe spins. We apply these results to the 1D Ising spin model with nearest-neighbor interaction which can be prepared on trapped atoms.

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A. R. Kuzmak, V. M. Tkachuk. 2019-03-26. Probing the Lee-Yang zeros of a spin bath by correlation functions and entanglement of two spins. https://doi.org/10.1088/1361-6455%2Fab3d6b

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