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arXiv · 2101.09235

Local Electronic Structure and Dynamics of Muon-Polaron Complexes in Fe$_2$O$_3$

M. H. Dehn·J. K. Shenton·D. J. Arseneau·W. A. MacFarlane·G. D. Morris·A. Maigné·N. A. Spaldin·R. F. Kiefl
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Abstract

We perform detailed muon spin rotation ($\mu$SR) measurements in the classic antiferromagnet Fe$_2$O$_3$ and explain the spectra by considering dynamic population and dissociation of charge-neutral muon-polaron complexes. We show that charge-neutral muon states in Fe$_2$O$_3$, despite lacking the signatures typical of charge-neutral muonium centers in nonmagnetic materials, have a significant impact on the measured $\mu$SR frequencies and relaxation rates. Our identification of such polaronic muon centers in Fe$_2$O$_3$ suggests that isolated hydrogen (H) impurities form analogous complexes, and that H interstitials may be a source of charge carrier density in Fe$_2$O$_3$.

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M. H. Dehn, J. K. Shenton, D. J. Arseneau, W. A. MacFarlane, G. D. Morris, A. Maigné, N. A. Spaldin, R. F. Kiefl. 2021-01-22. Local Electronic Structure and Dynamics of Muon-Polaron Complexes in Fe$_2$O$_3$. https://doi.org/10.1103/physrevlett.126.037202

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