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Infrared observation of the Hund's mechanism in an electron-doped manganite

A. Nucara·P. Calvani·F. Crispoldi·D. Sali·S. Lupi·C. Martin·A. Maignan
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Abstract

In the mid-infrared absorption of Sr{1-x}Ce{x}MnO{3} at low electron doping (x = 0.05), a band at 0.3 eV is fully replaced by another one at 0.9 eV as the system becomes antiferromagnetic (AF) of type $G$. A weaker effect occurs at x = 0.10 for an AF phase of type $C$. One thus directly measures the electron hopping energies for spin parallel and anti-parallel to that of the host ion. The Hund's, crystal-field, and Jahn-Teller splittings for the Mn{3+} ions in a Mn{4+} matrix, can also be derived.

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A. Nucara, P. Calvani, F. Crispoldi, D. Sali, S. Lupi, C. Martin, A. Maignan. 2006-01-25. Infrared observation of the Hund's mechanism in an electron-doped manganite. https://doi.org/10.1103/physrevb.73.054425

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