Spin correlations and entanglement in partially magnetised ensembles of fermions
Quantum Physics
2016-10-11 v2 Quantum Gases
Abstract
We show that the singlet fraction and total magnetisation (or polarisation) can bound the minimum concurrence in an ensemble of spins. We identify as a sufficient and tight condition for bipartite entanglement. Our proof makes no assumptions about the state of the system or symmetry of the particles, and can therefore be used as a witness for spin entanglement between fermions. We discuss the implications for recent experiments in which spin correlations were observed, and the prospect to study entanglement dynamics in the demagnetisation of a cold Fermi gas.
Keywords
Cite
@article{arxiv.1508.03570,
title = {Spin correlations and entanglement in partially magnetised ensembles of fermions},
author = {Guillaume S. Thekkadath and Liang Jiang and Joseph H. Thywissen},
journal= {arXiv preprint arXiv:1508.03570},
year = {2016}
}
Comments
10 pages, 1 figure; submitted to J. Phys. B (for the Special Issue on Addressing Quantum Many-body Problems with Cold Atoms and Molecules)