Raman spectroscopy of K x Co2-y Se2 single crystals near the ferromagnet-paramagnet transition.

  title={Raman spectroscopy of K x Co2-y Se2 single crystals near the ferromagnet-paramagnet transition.},
  author={M. Opa{\vc}i{\'c} and Nenad Lazarevi{\'c} and Milan Radonji{\'c} and Maja J. {\vS}{\'c}epanovi{\'c} and Hyejin Ryu and Aifeng Wang and D. Tanaskovi{\'c} and Cedomir Petrovic and Zoran V. Popovi{\'c}},
  journal={Journal of physics. Condensed matter : an Institute of Physics journal},
  volume={28 48},
Polarized Raman scattering spectra of the K x Co2-y Se2 single crystals reveal the presence of two phonon modes, assigned as of the A 1g and B 1g symmetry. The absence of additional modes excludes the possibility of vacancy ordering, unlike in K x Fe2-y Se2. The ferromagnetic (FM) phase transition at [Formula: see text] K leaves a clear fingerprint on the temperature dependence of the Raman mode energy and linewidth. For [Formula: see text] the temperature dependence looks conventional, driven… Expand
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