Vibrational, elastic, and structural properties of cubic silicon carbide under pressure up to 75 GPa: Implication for a primary pressure scale
Vibrational, elastic, and structural properties of cubic silicon carbide under pressure up to 75 GPa: Implication for a primary pressure scale
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DOI：
10.1063/1.4795348
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发表时间：
2013-03
影响因子：
3.2
通讯作者：
K. Zhuravlev;A. Goncharov;S. Tkachev;P. Dera;V. Prakapenka
中科院分区：
文献类型：
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作者：
K. Zhuravlev;A. Goncharov;S. Tkachev;P. Dera;V. Prakapenka
我们目前的同步辐射X射线衍射（XRD），布里渊，和拉曼光谱的立方碳化硅（3C-SiC）的单晶样品在准静水压力高达65 GPa，以及X射线衍射和拉曼光谱高达75 GPa的伴随测量结果。我们确定了3C-SiC的状态方程和压力依赖性的带心声子，弹性张量，和模式Gruneisen参数。立方SiC晶格被认为是稳定的高达75 GPa，但有一个倾向，不稳定超过40 GPa，基于软化的横向声速。通过应用伴随的密度和弹性测量，我们确定了SiC样品上的压力，而不参考任何其他压力标度，从而建立了一个新的初级压力标度，其精度为2%-4%，最高可达65 GPa。我们提出了现有的红宝石和氖的压力刻度的修正，并校准立方碳化硅作为压力标记的X射线衍射和拉曼实验。
We present results of concomitant measurements of synchrotron x-ray diffraction (XRD), Brillouin, and Raman spectroscopy on the single crystal samples of cubic silicon carbide (3C-SiC) under quasi-hydrostatic pressures up to 65 GPa, as well as x-ray diffraction and Raman spectroscopy up to 75 GPa. We determined the equation of state of 3C-SiC and pressure dependencies of the zone-center phonon, elastic tensor, and mode Gruneisen parameters. Cubic SiC lattice was found to be stable up to 75 GPa, but there is a tendency for destabilization above 40 GPa, based on softening of a transverse sound velocity. By applying the concomitant density and elasticity measurements, we determined the pressure on the SiC sample without referring to any other pressure scale thus establishing a new primary pressure scale with a 2%–4% precision up to 65 GPa. We proposed corrections to the existing ruby and neon pressure scales, and also calibrated cubic SiC as a pressure marker for the x-ray diffraction and Raman experiments.