Physical insight of superconductivity of Nb2AlC: in situ Raman spectrometry investigation
Physical insight of superconductivity of Nb2AlC: in situ Raman spectrometry investigation
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DOI：
10.1002/jrs.4196
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发表时间：
2013-03
影响因子：
2.5
通讯作者：
Huimin Xiang;Xiaohui Wang;Jingyang Wang;Yanchun Zhou
中科院分区：
文献类型：
--
作者：
Huimin Xiang;Xiaohui Wang;Jingyang Wang;Yanchun Zhou
Nb2AlC的超导性已有报道，但其起源尚不清楚。本文测量了Nb2AlC在室温80 ~ 380 K范围内的原位拉曼光谱。E2g （ω1）模的线宽随温度升高而增大，这是由非谐波声子-声子散射引起的。相反，E2g （ω2）和A1g （ω4）模式的线宽随着温度升高而不断减小。这种现象可以用电子-声子耦合来解释。因此，超导的起源可以通过Nb - 4d电子与E2g （ω2）和A1g （ω4）声子模式的耦合来解释。版权所有©2013 John Wiley & Sons， Ltd
Superconductivity of Nb2AlC has been previously reported, but the origin is not clear. In this paper, in situ Raman spectra of Nb2AlC are measured in the temperature range from 80 to 380 K at ambient pressure. The line-width of E2g (ω1) mode increases with temperature which originates from the anharmonic phonon–phonon scattering. On the contrary the line-widths of E2g (ω2) and A1g (ω4) modes decrease continuously at elevated temperature. The phenomenon is explained by the electron–phonon coupling. The origin of superconductivity is therefore interpreted by the coupling of Nb 4d electrons with E2g (ω2) and A1g (ω4) phonon modes. Copyright © 2013 John Wiley & Sons, Ltd.