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Acoustic Phonon Anomaly in MgB2

R. F. Wood·Bo E. Sernelius·A. L. Chernyshev
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Abstract

Recent first principles calculations of the phonon dispersion curves in MgB_2 have suggested the presence of anomalies in some of the curves, particularly in the longitudinal acoustical (LA) branch in the Gamma to A direction. Similar behavior has been observed in numerous other superconductors with T_c's higher than those of standard electron-phonon BCS superconductors. Phenomenological calculations of the Gamma->A LA dispersion based on both an acoustical plasmon and a ``resonant polarization'' mechanism are given here to emphasize the importance of these similarities.

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R. F. Wood, Bo E. Sernelius, A. L. Chernyshev. 2002-05-08. Acoustic Phonon Anomaly in MgB2. https://doi.org/10.1103/physrevb.66.014513

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