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arXiv · 1004.1616

Raman evidence for Orbiton-Mediated Multiphonon Scattering in Multiferroic TbMnO$_3$

Pradeep Kumar·Surajit Saha·D. V. S. Muthu·J. R. Sahu·A. K. Sood·C. N. R. Rao
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Abstract

Temperature-dependent Raman spectra of TbMnO$_3$ from 5 K to 300 K in the spectral range of 200 to 1525 cm$^{-1}$ show five first-order Raman allowed modes and two high frequency modes. The intensity ratio of the high frequency Raman band to the corresponding first order Raman mode is nearly constant and high ($\sim$ 0.6) at all temperatures, suggesting a orbiton-phonon mixed nature of the high frequency mode. One of the first order phonon modes shows anomalous softening below T$_N$ ($\sim$ 46 K), suggesting a strong spin-phonon coupling.

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Pradeep Kumar, Surajit Saha, D. V. S. Muthu, J. R. Sahu, A. K. Sood, C. N. R. Rao. 2010-04-09. Raman evidence for Orbiton-Mediated Multiphonon Scattering in Multiferroic TbMnO$_3$. https://doi.org/10.1088/0953-8984%2F22%2F11%2F115403

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