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arXiv · 0805.3241

Exchange energy dominated by large orbital spin-currents in $δ$-Pu

Francesco Cricchio·Fredrik Bultmark·Lars Nordström
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Abstract

The electronic structure of the anomalous $δ$-phase of Pu is analyzed by a general and exact reformulation of the exchange energy of the $f$-shell. It is found that the dominating contribution to the exchange energy is a polarization of orbital spin-currents that preserves the time reversal symmetry, hence a non-magnetic solution in accordance with experiments. The analysis brings a unifying picture of the role of exchange in the $5f$-shell with its relatively strong spin-orbit coupling. The results are in good accordance with recent measurements of the branching ratio for the $d$ to $f$ transition in the actinides.

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Francesco Cricchio, Fredrik Bultmark, Lars Nordström. 2008-05-21. Exchange energy dominated by large orbital spin-currents in $δ$-Pu. https://doi.org/10.1103/physrevb.78.100404

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