Possibility of coherent multiple excitation in atom transfer with a scanning tunneling microscope.
Possibility of coherent multiple excitation in atom transfer with a scanning tunneling microscope.
复制标题
使用扫描隧道显微镜进行原子转移中相干多重激发的可能性。
DOI：
10.1103/physrevb.49.10655
复制
发表时间：
1994
期刊：
影响因子：
--
通讯作者：
R. Palmer
中科院分区：
文献类型：
--
作者：
G. Salam;M. Persson;R. Palmer
我们研究原子转移所造成的吸附物基板键的非弹性隧穿的单个电子（或空穴）通过负（或正）离子共振的相干多重激发。在低偏压下，特别是对于导致原子转移的跃迁，相干多重激发的速率是非线性的，并且相对于偏压的极性也是高度不对称的。我们建立了一个简单的标准，该机制占主导地位的制度，在较早提出的机制，原子转移导致振动加热顺序（非相干）非弹性共振隧穿。在原子开关的情况下，在Ni表面和尖端之间转移的一个p2p原子，振动加热机制被发现占主导地位的相干机制。对于其他体系，如Na吸附在Cu上或O2吸附在Pt上，相干机制被认为在键断裂中起作用。
We examine atom transfer resulting from coherent multiple excitation of the adsorbate-substrate bond caused by inelastic tunneling of a single electron (or hole) via a negative-(or positive-) ion resonance. At low biases and in particular for the transitions resulting in atom transfer, the rates of coherent multiple excitation are nonlinear and also highly asymmetrical with respect to the polarity of the bias. We establish a simple criterion for the regime in which this mechanism dominates over earlier proposed mechanisms for atom transfer resulting from vibrational heating by sequential (incoherent) inelastic resonance tunneling. In the case of the atomic switch, where a Xe atom is transferred between a Ni surface and a tip, the vibrational heating mechanism is found to dominate over the coherent mechanism. For other systems, such as Na adsorption on Cu or O 2 adsorbed on Pt, the coherent mechanism is argued to play a role in bond breaking.