Bozhko Sergey I, Walshe Killian, Tulina Natalia, Walls Brian, Lübben Olaf, Murphy Barry E, Bozhko Vladimir, Shvets Igor V
Institute of Solid State Physics, Russian Academy of Sciences, Chernogolovka, Moscow District, 142432, Russia.
School of Physics and Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2, Ireland.
Sci Rep. 2019 Apr 17;9(1):6216. doi: 10.1038/s41598-019-42536-9.
Oxygen adatoms on the MoO/Mo(110) surface are observed to be removed when a sufficiently large bias is applied between the scanning tunneling microscope tip and the surface. Experimental observations, such as the bias polarity dependence of adatom removal and the observation of an intermediate state, indicate that the adatom penetrates the surface oxide layer. Through the comparison of finite element method simulations with various experimental relationships, the electric field is concluded to be the sole contributor to adatom penetration into the surface oxide layer. The energetic barrier to this process is estimated to be approximately 0.45 eV in magnitude. Furthermore, the resolution of this phenomenon is on the atomic scale: individual adatoms can undergo surface penetration whilst their nearest neighbour adatoms, separated by 5 Å, are unaffected. The mechanism reported here has the advantages of not strongly influencing the substrate and is exceptionally localised, which can be beneficial for the synthesis of single atom devices.
当在扫描隧道显微镜尖端与表面之间施加足够大的偏压时，观察到MoO/Mo(110)表面上的氧吸附原子会被去除。诸如吸附原子去除的偏压极性依赖性以及中间态的观察等实验观察结果表明，吸附原子会穿透表面氧化层。通过将有限元方法模拟与各种实验关系进行比较，得出电场是吸附原子穿透表面氧化层的唯一因素。据估计，这一过程的能量势垒大小约为0.45电子伏特。此外，这一现象的分辨率处于原子尺度：单个吸附原子能够进行表面穿透，而其相距5埃的最近邻吸附原子则不受影响。这里报道的机制具有不会强烈影响衬底且具有极高局部性的优点，这对于单原子器件的合成可能是有益的。
