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arXiv · 1112.5102

Optical properties and electronic structure of multiferroic hexagonal orthoferrites RFeO3 (R=Ho, Er, Lu)

V. V. Pavlov·A. R. Akbashev·A. M. Kalashnikova·V. A. Rusakov·A. R. Kaul·M. Bayer·R. V. Pisarev
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Abstract

We report on optical studies of the thin films of multiferroic hexagonal (P.G. 6mm) rare-earth orthoferrites RFeO3 (R=Ho, Er, Lu) grown epitaxially on a (111)-surface of ZrO2(Y2O3) substrate. The optical absorption study in the range of 0.6-5.6 eV shows that the films are transparent below 1.9 eV; above this energy four broad intense absorption bands are distinguished. The absorption spectra are analyzed taking into account the unusual fivefold coordination of the Fe(3+) ion. Temperature dependence of the optical absorption at 4.9 eV shows anomaly at 124 K, which we attribute to magnetic ordering of iron sublattices.

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V. V. Pavlov, A. R. Akbashev, A. M. Kalashnikova, V. A. Rusakov, A. R. Kaul, M. Bayer, R. V. Pisarev. 2012-07-17. Optical properties and electronic structure of multiferroic hexagonal orthoferrites RFeO3 (R=Ho, Er, Lu). https://doi.org/10.1063/1.3693588

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