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Pressure-induced phonon frequency shifts in transition-metal nitrides

Xiao-Jia Chen·Viktor V. Struzhkin·Simon Kung·Ho-kwang Mao·Russell J. Hemley·Axel N. Christensen
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Abstract

We report the first experiments on the high pressure phonon spectra of transition-metal nitrides HfN, ZrN, and NbN, obtained by Raman scattering measurements. Two pronounced bands, which are related to the acoustic part at low frequency around 200 cm$^{-1}$ and the optical part at high frequency around 550 cm$^{-1}$ of the phonon spectrum, respectively, shift to high frequency values with increasing pressure. An analysis of the results allows us to reproduce the experimental pressure dependence of the superconducting transition temperature $T_{c}$ of ZrN and NbN.

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Xiao-Jia Chen, Viktor V. Struzhkin, Simon Kung, Ho-kwang Mao, Russell J. Hemley, Axel N. Christensen. 2004-01-09. Pressure-induced phonon frequency shifts in transition-metal nitrides. https://doi.org/10.1103/physrevb.70.014501

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