Advanced Nanocharacterization Center, National Institute for Materials Science, Tsukuba, Ibaraki, Japan.
Nanotechnology. 2010 Jan 29;21(4):045707. doi: 10.1088/0957-4484/21/4/045707. Epub 2009 Dec 16.
We report on a multiple-state switching behavior in the tip height or tunneling current of scanning tunneling microscopy on the Si(111)-7 x 7 surface. This switching is caused by displacement of silicon adatoms under the influence of energetic tunneling electrons. When the tip is fixed over a center adatom, five well-defined levels appear in the measured tip height and tunneling current. These levels are attributed to different electronic structures, depending on the configuration of the center adatoms in the unit cell. We also demonstrate manipulations of the center adatoms by controlling the sample bias.
我们报告了在 Si(111)-7 x 7 表面的扫描隧道显微镜的尖端高度或隧道电流中的多重态切换行为。这种切换是由在高能隧道电子的影响下的硅吸附原子的位移引起的。当针尖固定在中心吸附原子上时，在测量的针尖高度和隧道电流中出现了五个明确定义的能级。这些能级归因于不同的电子结构，取决于单元胞中中心吸附原子的构型。我们还通过控制样品偏压来演示了对中心吸附原子的操纵。
