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arXiv · 0902.0867

Giant Kohn anomaly and the phase transition in charge density wave ZrTe_3

Moritz Hoesch·Alexey Bosak·Dmitry Chernyshov·Helmuth Berger·Michael Krisch
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Abstract

A strong Kohn anomaly in ZrTe_3 is identified in the mostly transverse acoustic phonon branch along the modulation vector q_P with polarization along the a* direction. This soft mode freezes to zero frequency at the transition temperature T_P and the temperature dependence of the frequency is strongly affected by fluctuation effects. Diffuse x-ray scattering of the incommensurate superstructure shows a power law scaling of the intensity and the correlation length that is compatible with an order parameter of dimension n = 2.

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Moritz Hoesch, Alexey Bosak, Dmitry Chernyshov, Helmuth Berger, Michael Krisch. 2009-02-05. Giant Kohn anomaly and the phase transition in charge density wave ZrTe_3. https://doi.org/10.1103/physrevlett.102.086402

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