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Raman scattering study of NaFe$_{0.53}$Cu$_{0.47}$As

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 نشر من قبل Weilu Zhang
 تاريخ النشر 2018
  مجال البحث فيزياء
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We use polarization-resolved Raman scattering to study lattice dynamics in NaFe$_{0.53}$Cu$_{0.47}$As single crystals. We identify 4 $A_{1g}$ phonon modes at 125, 172, 183 and 197 cm$^{-1}$, and 4 $B_{3g}$ phonon modes at 101, 138, 173, 226 cm$^{-1}$. The phonon spectra are consistent with the $Ibam$ group, which confirms that the Cu and Fe atoms form a stripe order. The temperature dependence of the phonon spectra suggests weak electron-phonon and magneto-elastic interactions.



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