Adams P W
Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
Phys Rev Lett. 2004 Feb 13;92(6):067003. doi: 10.1103/PhysRevLett.92.067003. Epub 2004 Feb 10.
We report spin-dependent electron density of states (DOS) studies of ultrathin superconducting Al and Be films in high parallel magnetic fields. Superconductor-insulator-superconductor (SIS) tunneling spectra are presented in which both the film and the counterelectrode are in the paramagnetic limit. This SIS configuration is exquisitely sensitive to spin mixing and/or spin flip processes which are manifest as DOS singularities at eV=2 Delta(0)+/-eV(z). Both our Al and Be data show a well defined subgap peak whose magnitude grows dramatically as the parallel critical field is approached. Though this feature has previously been attributed to spin-orbit scattering, it is more consistent with fluctuations into a field induced mixed-spin state.
我们报告了在高平行磁场中对超薄超导铝和铍薄膜的自旋相关电子态密度（DOS）研究。给出了超导体 - 绝缘体 - 超导体（SIS）隧穿谱，其中薄膜和对电极都处于顺磁极限。这种SIS结构对自旋混合和/或自旋翻转过程极其敏感，这些过程表现为在eV = 2Δ(0)±eV(z)处的DOS奇点。我们的铝和铍数据都显示出一个定义明确的亚能隙峰，当接近平行临界场时，其幅度会急剧增大。尽管这一特征此前被归因于自旋 - 轨道散射，但它更符合向场诱导混合自旋态的涨落。
