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arXiv · 0711.4744

On the question of ferromagnetism in alkali metal thin films

Prasenjit Sen
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Abstract

Electronic and magnetic structure of $(100)$ films of K and Cs are calculated within the plane-wave projector augmented wave (PAW) formalism of the density functional theory (DFT) using both local spin density approximation (LSDA) and the PW91 generalized gradient approximation (GGA). Only a 6 layer Cs film is found to have a ferromagnetic (FM) state which is degenerate with a paramagnetic (PM) state within the accuracy of these calculations. This is at variance with the results obtained from a finite thickness uniform jellium model (UJM). Implications of these results for the experiments on transition metal doped alkali metal thin films and bulk hosts are discussed.

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Prasenjit Sen. 2007-11-29. On the question of ferromagnetism in alkali metal thin films. https://arxiv.org/abs/0711.4744

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