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arXiv · 2001.10607

Many-particle Entanglement in Multiple Quantum NMR Spectroscopy

S. I. Doronin·E. B Fel'dman·I. D. Lazarev
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Abstract

We use multiple quantum (MQ) NMR dynamics of a gas of spin-carrying molecules in nanocavities at high and low temperatures for an investigation of many-particle entanglement. A distribution of MQ NMR intensities is obtained at high and low temperatures in a system of 201 spins 1/2. The second moment of the distribution, which provides a lower bound on the quantum Fisher information, sheds light on the many-particle entanglement in the system. The dependence of the many-particle entanglement on the temperature is investigated. Almost all spins are entangled at low temperatures.

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S. I. Doronin, E. B Fel'dman, I. D. Lazarev. 2020-01-28. Many-particle Entanglement in Multiple Quantum NMR Spectroscopy. https://doi.org/10.1103/physreva.100.022330

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