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arXiv · 0707.3614

Terahertz spectroscopy of electromagnons in Eu_{1-x}Y_xMnO_3

A. Pimenov·A. Loidl·A. A. Mukhin·V. D. Travkin·V. Yu. Ivanov·A. M. Balbashov
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Abstract

Dielectric permittivity spectra of yttrium-doped EuMnO$_3$ in the composition range 0 =< x =< 0.5 have been investigated in the terahertz frequency range. Magnetoelectric contributions to the permittivity were observed in all compositions for ac electric fields parallel to the crystallographic a-axis. Well defined electromagnons exist for x >= 0.2 close to ν~ 20 cm^{-1} and with dielectric strength strongly increasing on doping. In addition to electromagnons, a broad contribution of magnetoelectric origin is observed for all compositions. For Eu_{0.8}Y_{0.2}MnO_3 the electromagnons can be suppressed by external magnetic fields which induce a canted antiferromagnetic phase. Magnetoelectric effects in the different doping regimes are discussed in detail.

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A. Pimenov, A. Loidl, A. A. Mukhin, V. D. Travkin, V. Yu. Ivanov, A. M. Balbashov. 2007-07-24. Terahertz spectroscopy of electromagnons in Eu_{1-x}Y_xMnO_3. https://doi.org/10.1103/physrevb.77.014438

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