论文标题
弱拓扑绝缘体BI2TEI和拓扑金属BI3TEI中的压力诱导的超导性
Pressure-induced superconductivity in the weak topological insulator Bi2TeI and the topological metal Bi3TeI
论文作者
论文摘要
我们报告了一系列高压电运输，磁化率和X射线衍射测量，这些测量值和弱拓扑绝缘子BI2TEI和拓扑金属BI3TEI上的单晶进行了测量。室温X射线衍射测量表明，两种材料都经过一系列压力诱导的结构过渡，并最终在高压下采用无序的BCC合金结构。与先前建议的P4/NMM结构相比，对Bitei的已发表数据的重新分析表明，该材料在高压下也采用了无序的BCC结构。我们发现BI2TEI和BI3TEI分别在13 GPA和11.5 GPA的超导下成为超导。在两种情况下，BCC相的超导临界温度TC分别达到BI2TEI和BI3TEI的最大值为7 K和7.5 K，而DTC/DP <0分别达到最大值。结果表明，高压下BI-TE和BI-TE-I系统的合金BCC超导阶段似乎是普遍特征。
We report a series of high-pressure electrical transport, magnetic susceptibility, and x-ray diffraction measurements on single crystals of the weak topological insulator Bi2TeI and the topological metal Bi3TeI. Room temperature x-ray diffraction measurements show that both materials go through a series of pressure-induced structural transitions and eventually adopt a disordered bcc alloy structure at high pressure. A re-analysis of the published data on BiTeI indicates that this material also adopts a disordered bcc structure at high pressure, in contrast to the previously suggested P4/nmm structure. We find that Bi2TeI and Bi3TeI become superconducting at 13 GPa and 11.5 GPa, respectively. The superconducting critical temperature Tc of the bcc phase reaches maximum values of 7 K and 7.5 K for Bi2TeI and Bi3TeI, respectively and dTc/dP < 0 in both cases. The results indicate that disordered alloy bcc superconducting phases appear to be a universal feature of both the Bi-Te and Bi-Te-I systems at high pressure.
