论文标题
非中心对称NBGE $ _ {2} $中的I类超导性
Type-I superconductivity in noncentrosymmetric NbGe$_{2}$
论文作者
论文摘要
NBGE $ _ {2} $的单晶体在非中心对称六角形结构中结晶具有手性，并研究了其超导性。通过DC磁化，特定热量中野外诱导的二阶相变和小的Ginzburg-Landau参数$κ_{GL} = 0.12 $确认了I型超导性。等温磁化测量结果表明，从I型到II/1型超导性的跨界均随温度降低，并且发现了异常增强的表面超导临界场（$ H_ {C3} $）。带结构计算表明在费米水平附近存在kramer-weyl节点。这些观察结果表明，nbge $ _ {2} $是一个有趣而罕见的例子，涉及I型超导性，非中心对称结构和拓扑特性的可能相互作用。
Single crystals of NbGe$_{2}$ which crystallize in a noncentrosymmetric hexagonal structure with chirality are synthesized and their superconductivity is investigated. Type-I superconductivity is confirmed by dc magnetization, field-induced second-to first-order phase transition in specific heat, and a small Ginzburg-Landau parameter $κ_{GL}=0.12$. The isothermal magnetization measurements show that there is a crossover from type-I to type-II/1 superconductivity with decreasing temperature and an unusually enhanced surface superconducting critical field ($H_{c3}$) is discovered. The band structure calculations indicate the presence of Kramer-Weyl nodes near the Fermi level. These observations demonstrate that NbGe$_{2}$ is an interesting and rare example involving the possible interplay of type-I superconductivity, noncentrosymmetric structure and topological properties.
