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arXiv · 1210.1343

THz spectroscopy in the pseudo-Kagome system Cu3Bi(SeO3)2O2Br

Zhe Wang·M. Schmidt·Y. Goncharov·V. Tsurkan·H. -A. Krug von Nidda·A. Loidl·J. Deisenhofer
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Abstract

Terahertz (THz) transmission spectra have been measured as function of temperature and magnetic field on single crystals of Cu3Bi(SeO3)2O2Br. In the time-domain THz spectra without magnetic field, two resonance absorptions are observed below the magnetic ordering temperature T_N~27.4 K. The corresponding resonance frequencies increase with decreasing temperature and reach energies of 1.28 and 1.23 meV at 3.5 K. Multi-frequency electron spin resonance transmission spectra as a function of applied magnetic field show the field dependence of four magnetic resonance modes, which can be modeled as a ferromagnetic resonance including demagnetization and anisotropy effects.

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Zhe Wang, M. Schmidt, Y. Goncharov, V. Tsurkan, H. -A. Krug von Nidda, A. Loidl, J. Deisenhofer. 2012-11-13. THz spectroscopy in the pseudo-Kagome system Cu3Bi(SeO3)2O2Br. https://doi.org/10.1103/physrevb.86.174411

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