吉林大学刘冰冰团队报道了压力调谐Bi₂O₂Se平带诱导超导。相关研究成果发表在2024年3月6日出版的《美国化学会杂志》。

扭曲双层石墨烯中超导性的发现重新点燃了平带超导领域的热情。然而，重要的挑战仍然存在，例如构建平带结构和在材料中诱导超导状态。

该文中，研究人员通过对平带电子结构进行压力调谐，成功地在Bi₂O₂Se中实现了超导性。实验测量与理论计算相结合表明，30GPa压力诱导超导电性的发生与费米能级附近的平带电子结构有关。此外，在Bi₂O₂Se中，在费米能级观察到范霍夫奇点，同时观察到明显的费米表面嵌套。

这些显著的特征在促进强电子-声子相互作用方面发挥着至关重要的作用，从而有可能增强材料的超导性能。这些发现表明，压力为精确调谐平带和实现超导性提供了一种潜在的实验策略。

附：英文原文

Title: Tuning the Flat Band in Bi2O2Se by Pressure to Induce Superconductivity

Author: Hui Tian, Teng Tu, Xilian Jin, Chenyi Li, Tao Lin, Qing Dong, Xiaoling Jing, Bo Liu, Ran Liu, Da Li, Zhongkai Liu, Quanjun Li, Hailin Peng, Bingbing Liu

Issue&Volume: March 6, 2024

Abstract: The discovery of superconductivity in twisted bilayer graphene has reignited enthusiasm in the field of flat-band superconductivity. However, important challenges remain, such as constructing a flat-band structure and inducing a superconducting state in materials. Here, we successfully achieved superconductivity in Bi2O2Se by pressure-tuning the flat-band electronic structure. Experimental measurements combined with theoretical calculations reveal that the occurrence of pressure-induced superconductivity at 30 GPa is associated with a flat-band electronic structure near the Fermi level. Moreover, in Bi2O2Se, a van Hove singularity is observed at the Fermi level alongside pronounced Fermi surface nesting. These remarkable features play a crucial role in promoting strong electron–phonon interactions, thus potentially enhancing the superconducting properties of the material. These findings demonstrate that pressure offers a potential experimental strategy for precisely tuning the flat band and achieving superconductivity.

DOI: 10.1021/jacs.3c11984

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.3c11984