论文标题
超导低携带者密度准密度kutterudite lu3os4ge13中的时间反转对称性破裂13
Time-reversal symmetry breaking in superconducting low-carrier-density quasi-skutterudite Lu3Os4Ge13
论文作者
论文摘要
Remeika相的复杂结构，它们所显示的有趣的量子状态以及低载体浓度是研究其超导相的性质的强大动力。在这项工作中，单晶lu $ _3 $ os $ _4 $ ge $ _ {13} $的超导阶段的显微镜特性通过muon-spin放松和旋转（$μ$ $ sr）的测量进行了研究。零场$μ$ SR数据揭示了超导状态下的自发静态或准静态磁场的存在，破坏了时间反转对称性。发现相关的内部磁场尺度非常大（$ \ $ \ $ 0.18〜mt）。此外，在vortex状态下的横向场$ $ $ $ SR测量值_3 $ _4 $ _4 $ ge $ _ {13} $表示复杂的间隙功能，在费米表面的不同部分上具有明显不同的优势。尽管我们的测量结果并不能完全确定顺序参数，但它们强烈表明电子 - 电子相互作用对于稳定系统中的配对至关重要，因此证明其非常规性。
The complex structure of the Remeika phases, the intriguing quantum states they display, and their low carrier concentrations are a strong motivation to study the nature of their superconducting phases. In this work, the microscopic properties of the superconducting phase of single-crystalline Lu$_3$Os$_4$Ge$_{13}$ are investigated by muon-spin relaxation and rotation ($μ$SR) measurements. The zero-field $μ$SR data reveal the presence of spontaneous static or quasi-static magnetic fields in the superconducting state, breaking time-reversal symmetry; the associated internal magnetic field scale is found to be exceptionally large ($\approx$ 0.18~mT). Furthermore, transverse-field $μ$SR measurements in the vortex state of Lu$_3$Os$_4$Ge$_{13}$ imply a complex gap function with significantly different strengths on different parts of the Fermi surface. While our measurements do not completely determine the order parameter, they strongly indicate that electron-electron interactions are essential to stabilizing pairing in the system, thus, demonstrating its unconventional nature.
