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Ferromagnetic instabilities in atomically-thin lithium and sodium wires

A. Bergara·J. B. Neaton·N. W. Ashcroft
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Abstract

Using density functional theory the ground state structural, electronic, and magnetic properties of monatomic lithium and sodium chains with low average density are investigated. A metallic, zigzag ground state structure is predicted but, most interestingly, stable equilibria for chains under tension are predicted to be {\it ferromagnetic}, which can be traced to exchange effects arising from occupation of the second subband as a function of the interatomic distance.

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A. Bergara, J. B. Neaton, N. W. Ashcroft. 2002-10-09. Ferromagnetic instabilities in atomically-thin lithium and sodium wires. https://arxiv.org/abs/cond-mat/0103499

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