Article

# Spin Resonance in EuTiO3 Probed by Time-Domain Gigahertz Ellipsometry

Département de Physique de la Matière Condensée, Université de Genève, Genève, Switzerland.
(Impact Factor: 7.51). 05/2011; 106(21):217601. DOI: 10.1103/PhysRevLett.106.217601
Source: PubMed

ABSTRACT We show an example of a purely magnetic spin resonance in EuTiO(3) and the resulting new record high Faraday rotation of 590°/mm at 1.6 T for 1 cm wavelengths probed by a novel technique of magneto-optical gigahertz time-domain ellipsometry. From our transmission measurements of linear polarized light, we map out the complex index of refraction n=√ϵμ in the gigahertz to terahertz 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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