Spin polarization of graphene and h-BN on Co(0001) and Ni(111) observed by spin-polarized surface positronium spectroscopy
Spin polarization of graphene and h-BN on Co(0001) and Ni(111) observed by spin-polarized surface positronium spectroscopy
复制标题
自旋极化表面正电子能谱观察Co(0001)和Ni(111)上石墨烯和h-BN的自旋极化
DOI：
10.1103/physrevb.97.195405
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发表时间：
2018
影响因子：
3.7
通讯作者：
S. Sakai
中科院分区：
文献类型：
--
作者：
A. Miyashita;M. Maekawa;K. Wada;A. Kawasuso;S. Entani;T. Watanabe;S. Sakai
在自旋极化表面正电子湮灭测量中，石墨烯和bn在Co（0001）上的自旋极化高于Ni（111）上的自旋极化，而在同一金属上石墨烯和bn之间没有显著差异。考虑到正电子波函数和从第一表层到真空区的电子态密度，得到的自旋极化与第一性原理计算的结果一致。与Ni（111）相比，石墨烯和bn在Co（0001）上的高自旋极化仅仅反映了这些金属的自旋极化。石墨烯和氮化硼在同一金属上的类似自旋极化是由于金属的强烈影响产生了类似的电子态：石墨烯的狄拉克锥和氮化硼的带隙由于杂化而消失。
In spin-polarized surface positronium annihilation measurements, the spin polarizations of graphene and-BN on Co(0001) were higher than those on Ni(111), while no significant differences were seen between graphene and-BN on the same metal. The obtained spin polarizations agreed with those expected from first-principles calculations considering the positron wave function and the electron density of states from the first surface layer to the vacuum region. The higher spin polarizations of graphene and-BN on Co(0001) as compared to Ni(111) simply reflect the spin polarizations of these metals. The comparable spin polarizations of graphene and-BN on the same metal are attributed to the creation of similar electronic states due to the strong influence of the metals: the Dirac cone of graphene and the band gap of-BN disappear as a consequence ofhybridization.