标题： 压致非中心对称外尔半金属LaAlX（X = Si和Ge）的超导性 显示英文标题

标题： Pressure-induced Superconductivity in Noncentrosymmetric Weyl Semimetals LaAlX (X = Si and Ge)

摘要： 在拓扑材料中，由于空间反演对称性的破坏，狄拉克费米子可以分裂成两种手性相反的外尔费米子。而在非中心对称超导体中，由于反对称自旋轨道耦合，会出现新的超导电子配对机制。 在这项工作中，我们报告了一种典型的非中心对称外尔半金属LaAlX（X=Si和Ge）中压力引入的超导性。在约65 GPa下观察到了超导性，而没有结构相变。获得了典型的穹顶形状相图，LaAlSi（LaAlGe）的最大Tc分别为2.5 K（2.1 K）。此外，压力的应用不会破坏LaAlSi在80.4 GPa以内的非平凡能带拓扑结构，使这类材料成为实现拓扑超导性的潜在候选者。 我们在LaAlX（X=Si和Ge）中发现的超导性将为非中心对称超导体提供关键见解，并激发对外尔半金属中超导性的进一步研究。 显示英文摘要

摘要： In topological materials, Dirac fermions can split into two Weyl fermions with opposite chiralities due to the breaking of space inversion symmetry, while in non-centrosymmetric superconductors, novel superconducting electron pairing mechanisms arise because of the antisymmetric spin-orbit coupling. In this work, we report the pressure-introduced superconductivity in a typical noncentrosymmetric Weyl semimetal LaAlX (X=Si and Ge). Superconductivity was observed at around 65 GPa without structural phase transition. A typical dome-shape phase diagram is obtained with the maximum Tc of 2.5 K (2.1 K) for LaAlSi (LaAlGe). Furthermore, the application of pressure does not destroy the nontrivial band topology of LaAlSi up to 80.4 GPa, making such materials as potential candidates for realizing topological superconductivity. Our discovery of superconductivity in LaAlX (X=Si and Ge) will provide critical insight in noncentrosymmetric superconductors and stimulate further study on superconductivity in Weyl semimetals.