Pressure-induced superconductivity in a novel germanium allotrope
Pressure-induced superconductivity in a novel germanium allotrope
复制标题
DOI：
10.1016/j.mtphys.2024.101338
复制
发表时间：
2024-01
影响因子：
11.5
通讯作者：
L. Deng;Jianbo Zhang;Yuki Sakai;Zhongjia Tang;M. Adnani;R. Dahal;A. Litvinchuk;J. Chelikowsky;Marvin L. Cohen;R. Hemley;A. Guloy;Yang Ding;Ching-Wu Chu
中科院分区：
文献类型：
--
作者：
L. Deng;Jianbo Zhang;Yuki Sakai;Zhongjia Tang;M. Adnani;R. Dahal;A. Litvinchuk;J. Chelikowsky;Marvin L. Cohen;R. Hemley;A. Guloy;Yang Ding;Ching-Wu Chu
元素的高压研究在超导研究中起着至关重要的作用，对基础科学和应用都有影响。在这里，我们报告的实验发现，令人惊讶的低压力驱动一个新的锗同素异形体进入超导状态相比，α-Ge。拉曼测量揭示了结构相变和可能的电子拓扑转变的压力下高达58 GPa。基于压力相关的电阻率测量，超导诱导高于2GPa和最大Tc的6.8K下观察到4.6GPa。有趣的是，在减压过程中发现了超导性增强，这表明在环境压力下保持压力诱导超导性的可能性具有更好的超导性能。密度泛函理论分析进一步表明，Ge（oP 32）的电子结构对其详细的几何形状敏感，并揭示了β-tin结构中的无序导致与完美的β-tin Ge相比更高的Tcin。
High-pressure studies on elements play an essential role in superconductivity research, with implications for both fundamental science and applications. Here we report the experimental discovery of surprisingly low pressure driving a novel germanium allotrope into a superconducting state in comparison to that for α-Ge. Raman measurements revealed structural phase transitions and possible electronic topological transitions under pressure up to 58 GPa. Based on pressure-dependent resistivity measurements, superconductivity was induced above 2 GPa and the maximum Tcof 6.8 K was observed under 4.6 GPa. Interestingly, a superconductivity enhancement was discovered during decompression, indicating the possibility of maintaining pressure-induced superconductivity at ambient pressure with better superconducting performance. Density functional theory analysis further suggested that the electronic structure of Ge (oP32) is sensitive to its detailed geometry and revealed that disorder in the β-tin structure leads to a higher Tcin comparison to the perfect β-tin Ge.