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arXiv · 1409.7067

Entanglement and spin squeezing in non-Hermitian phase transitions

Tony E. Lee·Florentin Reiter·Nimrod Moiseyev
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Abstract

We show that non-Hermitian dynamics generate substantial entanglement in many-body systems. We consider the non-Hermitian Lipkin-Meshkov-Glick model and show that its phase transition occurs with maximum multiparticle entanglement: there is full N-particle entanglement at the transition, in contrast to the Hermitian case. The non-Hermitian model also exhibits more spin squeezing than the Hermitian model, showing that non-Hermitian dynamics are useful for quantum metrology. Experimental implementations with trapped ions and cavity QED are discussed.

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Tony E. Lee, Florentin Reiter, Nimrod Moiseyev. 2014-12-17. Entanglement and spin squeezing in non-Hermitian phase transitions. https://doi.org/10.1103/physrevlett.113.250401

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