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Dynamics of the Peierls-active phonon modes in CuGeO_3

Claudius Gros·Ralph Werner
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Abstract

We reconsider the Cross and Fischer approach to spin-Peierls transitions. We show that a soft phonon occurs only if Omega_0<2.2 T_SP. For CuGeO_3 this condition is not fulfilled and the calculated temperature dependence of the Peierls-active phonon modes is in excellent agreement with experiment. A central peak of a width ~0.2 meV is predicted at T_SP. Good agreement is found between theory and experiment for the pretransitional Peierls-fluctuations. Finally, we consider the problem of quantum criticality in CuGeO_3.

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Claudius Gros, Ralph Werner. 1998-04-08. Dynamics of the Peierls-active phonon modes in CuGeO_3. https://doi.org/10.1103/physrevb.58.r14677

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