Stress-induced nematicity in EuFe 2 As 2 studied by Raman spectroscopy
Stress-induced nematicity in EuFe 2 As 2 studied by Raman spectroscopy
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拉曼光谱研究EuFe 2 As 2 中应力诱导向列性
DOI：
10.1103/physrevb.94.014513
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发表时间：
2016
影响因子：
3.7
通讯作者：
G. Blumberg
中科院分区：
文献类型：
--
作者：
W.;A. Sefat;H. Ding;P. Richard;G. Blumberg
我们用偏振喇曼散射研究了122铁烟酸铁电超导体的母体化合物{MATHROM{EuFe}}{MATHROM{As}}{2}$中的结构相变。面内晶格各向异性是通过测量不同制备方法引起的不同应变的侧面来表征的。结果表明，虽然表面抛光使样品没有残余的内部应变，在这种情况下，在标称结构相变温度${T}_{S}$处观察到对称性破缺的开始，但切割侧面导致了跨越${T}_{S}$数十度的永久性四重旋转对称性破缺。
We use polarized Raman scattering to study the structural phase transition in ${\mathrm{EuFe}}_{2}{\mathrm{As}}_{2}$, the parent compound of the 122-ferropnictide superconductors. The in-plane lattice anisotropy is characterized by measurements of the side surface with different strains induced by different preparation methods. We show that while a fine surface polishing leaves the samples free of residual internal strain, in which case the onset of the ${C}_{4}$ symmetry breaking is observed at the nominal structural phase transition temperature ${T}_{S}$, cutting the side surface induces a permanent fourfold rotational symmetry breaking spanning tens of degrees above ${T}_{S}$.