Ke Feng, Niu Shanyuan, Feng Jiajia, Yin Ketao, Han Minkyung, Yang Hong, Wang Bai Yang, Celeste Anna, Jia Chunjing, Chen Bin, Wang Lin, Hwang Harold Y, Tian Yongjun, Mao Wendy L, Lin Yu
Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA.
State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, Hebei 066004, China.
Sci Adv. 2025 Sep 12;11(37):eadv1894. doi: 10.1126/sciadv.adv1894.
Oxide perovskite superconductors typically feature stacks of metal-oxygen octahedra or planar blocks connected through corners, forming three-dimensional (3D) or 2D layered structures. Here, we find a group of quasi-1D superconducting materials among hexagonal perovskite chalcogenides with face-sharing connectivity. Resistance and magnetization measurements demonstrate anisotropic superconductivity in compressed barium titanium trisulfide (BaTiS) at a low hole carrier concentration of (1.6 ± 0.1) × 10 per cubic centimeter, with the highest superconducting temperature () reaching ~9.3 kelvin. Synchrotron x-ray diffraction indicates that the superconducting phase retains a hexagonal perovskite structure consisting of quasi-1D infinite titanium hexasulfide chains. Density functional theory calculations, combined with the observed decrease in the maximum from ~9.3 to ~6.2 kelvin upon substituting sulfur with selenium, suggest that electron-phonon interactions play a key role in the pairing mechanism of superconducting BaTiX (X = sulfur and selenium). Our study offers a quasi-1D platform with face-sharing metal-chalcogen octahedra for understanding the mechanism of emerging electronic states in perovskite materials.
钙钛矿氧化物超导体通常具有通过角连接的金属 - 氧八面体或平面块的堆叠，形成三维（3D）或二维层状结构。在这里，我们在具有面共享连接性的六方钙钛矿硫族化物中发现了一组准一维超导材料。电阻和磁化测量表明，在低空穴载流子浓度为（1.6±0.1）×10每立方厘米的压缩三硫化钡钛（BaTiS）中存在各向异性超导性，最高超导温度（）达到约9.3开尔文。同步加速器X射线衍射表明，超导相保留了由准一维无限六硫化钛链组成的六方钙钛矿结构。密度泛函理论计算，结合用硒替代硫时观察到的最大值从约9.3开尔文降至约6.2开尔文的情况，表明电子 - 声子相互作用在超导BaTiX（X =硫和硒）的配对机制中起关键作用。我们的研究提供了一个具有面共享金属 - 硫族八面体的准一维平台，用于理解钙钛矿材料中新兴电子态的机制。
