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Infrared reflectivity of pure and doped CuGeO3

A. Damascelli·D. van der Marel·F. Parmigiani·G. Dhalenne·A. Revcolevschi
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Abstract

We investigated the far- and mid-infrared reflectivity (20-6000 wavenumber) of several pure and doped CuGeO3 single crystals. The b-axis and c-axis optical response is presented for different temperatures between 4 K and 300 K. Moreover, a full group theoretical analysis of the lattice vibrational modes of CuGeO3 in the high temperature undistorted phase as well as in the low temperature spin-Peierls phase is reported and compared to the experimental results. We observe the activation of zone boundary phonons along the b axis of the crystal below the spin-Peierls transition temperature.

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A. Damascelli, D. van der Marel, F. Parmigiani, G. Dhalenne, A. Revcolevschi. 1997-07-31. Infrared reflectivity of pure and doped CuGeO3. https://doi.org/10.1016/s0921-4526(97)00472-9

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