Spin-polarized surface states of germanium substrate modified by surface adsorbates

研究了重元素原子吸附半导体衬底的自旋极化表面态。单层Pb吸附的Ge（111）表面显示出定位于Ge（111）衬底亚表层的二维电子态。此外，由于Rashba效应，表面态能带被分成两个。对于在Ge（001）表面形成的pt诱导纳米线，我们发现了几个一维金属带。其中一个金属带精确地是一维的，表现为费米气体。另外，另一个准一维金属带表现出rashba型自旋分裂。这些结果对于表面自旋输运、过滤和注入半导体等新的科学领域至关重要。

Spin-polarized surface states of heavy-element-atoms adsorbed semiconductor substrates have been studied. A monolayer Pb adsorbed Ge(111) surface exhibits two-dimensional electronic states localized in subsurface layers of a Ge(111) substrate. In addition, the surface-state bands are split into two due to the Rashba effect. For Pt-induced nanowires formed on Ge(001) surface, we found several one-dimensional metallic bands. One of the metallic bands is accurately one-dimensional and behaves as the Fermi gas. In addition, another quasi-one-dimensional metallic band shows the Rashba-type spin splitting. These results are essential to a new scientific field such as surface spin transport, filtering and injection into semiconductors.