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arXiv · 2302.09829

Spin squeezing in open Heisenberg spin chains

Tanausú Hernández Yanes·Giedrius Žlabys·Marcin Płodzień·Domantas Burba·Mažena Mackoit Sinkevičienė·Emilia Witkowska·Gediminas Juzeliūnas
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Abstract

Spin squeezing protocols successfully generate entangled many-body quantum states, the key pillars of the second quantum revolution. In our recent work [Phys. Rev. Lett. 129, 090403 (2022)] we showed that spin squeezing described by the one-axis twisting model could be generated in the Heisenberg spin-1/2 chain with periodic boundary conditions when accompanied by a position-dependent spin-flip coupling induced by a single laser field. This work shows analytically that the change of boundary conditions from the periodic to the open ones significantly modifies spin squeezing dynamics. A broad family of twisting models can be simulated by the system in the weak coupling regime, including the one- and two-axis twisting under specific conditions, providing the Heisenberg level of squeezing and acceleration of the dynamics. Full numerical simulations confirm our analytical findings.

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Tanausú Hernández Yanes, Giedrius Žlabys, Marcin Płodzień, Domantas Burba, Mažena Mackoit Sinkevičienė, Emilia Witkowska, Gediminas Juzeliūnas. 2023-02-20. Spin squeezing in open Heisenberg spin chains. https://doi.org/10.1103/physrevb.108.104301

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