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Phonon dispersion and lifetimes in MgB2

Abhay Shukla·Matteo Calandra·Matteo d'Astuto·Michele Lazzeri·Francesco Mauri·Christophe Bellin·Michael Krisch·J. Karpinski·S. M. Kazakov·J. Jun·D. Daghero·K. Parlinski
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Abstract

We measure phonon dispersion and linewidth in a single crystal of MgB_2 along the Gamma-A, Gamma-M and A-L directions using inelastic X-Ray scattering. We use Density Functional Theory to compute the effect of both electron-phonon coupling and anharmonicity on the linewidth, obtaining excellent agreement with experiment. Anomalous broadening of the E_2g phonon mode is found all along Gamma-A. The dominant contribution to the linewidth is always the electron-phonon coupling.

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Abhay Shukla, Matteo Calandra, Matteo d'Astuto, Michele Lazzeri, Francesco Mauri, Christophe Bellin, Michael Krisch, J. Karpinski, S. M. Kazakov, J. Jun, D. Daghero, K. Parlinski. 2003-01-07. Phonon dispersion and lifetimes in MgB2. https://doi.org/10.1103/physrevlett.90.095506

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