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arXiv · 1105.3553

Spin resonance in EuTiO3 probed by time-domain GHz ellipsometry

J. L. M. van Mechelen·D. van der Marel·I. Crassee·T. Kolodiazhnyi
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Abstract

We show an example of a purely magnetic spin resonance in EuTiO3 and the resulting new record high Faraday rotation of 590 deg/mm at 1.6 T for 1 cm wavelengths probed by a novel technique of magneto-optical GHz time-domain ellipsometry. From our transmission measurements of linear polarized light we map out the complex index of refraction in the GHz to THz range. We observe a strong resonant absorption by magnetic dipole transitions involving the Zeeman split S=7/2 magnetic energy levels of the Eu 2+ ions, which causes a very large dichroism for circular polarized radiation.

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J. L. M. van Mechelen, D. van der Marel, I. Crassee, T. Kolodiazhnyi. 2011-05-18. Spin resonance in EuTiO3 probed by time-domain GHz ellipsometry. https://doi.org/10.1103/physrevlett.106.217601

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