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Far-Infrared Spectroscopy in Spin-Peierls Compound CuGeO_3 under High Magnetic Fields

K. Takehana·T. Takamasu·M. Hase·G. Kido·K. Uchinokura
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Abstract

Polarized far-infrared (FIR) spectroscopic measurements and FIR magneto-optical studies were performed on the inorganic spin-Peierls compound CuGeO_3. An absorption line, which was found at 98 cm$^{-1}$ in the dimerized phase (D phase), was assigned to a folded phonon mode of B$_{3u}$ symmetry. The splitting of the folded mode into two components in the incommensurate phase (IC phase) has been observed for the first time. A new broad absorption centered at 63 cm$^{-1}$ was observed only in the ${\bf E}\parallel b$ axis polarization, which was assigned to a magnetic excitation from singlet ground state to a continuum state.

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K. Takehana, T. Takamasu, M. Hase, G. Kido, K. Uchinokura. 2000-03-20. Far-Infrared Spectroscopy in Spin-Peierls Compound CuGeO_3 under High Magnetic Fields. https://doi.org/10.1103/physrevb.62.5191

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