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Raman spectrum and lattice parameters of MgB2 as a function of pressure

Alexander F. Goncharov·Viktor V. Struzhkin·Eugene Gregoryanz·Jingzhu Hu·Russell J. Hemley·Ho-kwang Mao·G. Lapertot·S. L. Bud'ko·P. C. Canfield
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Abstract

We report Raman spectra and synchrotron x-ray diffraction measurements of lattice parameters of polycrystalline MgB2 under hydrostatic pressure conditions up to 15 GPa. An anomalously broadened Raman band at 620 cm-1 is observed that exhibits a large linear pressure shift of its frequency. The large mode damping and Gruneisen parameter indicate a highly anharmonic nature of the mode, broadly consistent with theoretical predictions for the E2g in-plane boron stretching mode. The results obtained may provide additional constraints on the electron-phonon coupling in the system.

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Alexander F. Goncharov, Viktor V. Struzhkin, Eugene Gregoryanz, Jingzhu Hu, Russell J. Hemley, Ho-kwang Mao, G. Lapertot, S. L. Bud'ko, P. C. Canfield. 2001-04-04. Raman spectrum and lattice parameters of MgB2 as a function of pressure. https://doi.org/10.1103/physrevb.64.100509

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