Quantum transport in an atom-sized bridge between a metal surface and a tip of a scanning tunneling microscope at finite temperatures
Quantum transport in an atom-sized bridge between a metal surface and a tip of a scanning tunneling microscope at finite temperatures
复制标题
有限温度下金属表面和扫描隧道显微镜尖端之间原子大小的桥中的量子传输
DOI：
10.1063/1.369215
复制
发表时间：
1999
影响因子：
3.2
通讯作者：
A. Okiji
中科院分区：
文献类型：
--
作者：
Y. Kawahito;H. Kasai;H. Nakanishi;A. Okiji
本文用Hubbard哈密顿量研究了扫描隧道显微镜针尖与金属表面之间原子大小的桥中电子输运，着重讨论了桥内库仑相互作用对电子输运的影响。在计算桥的电导时，考虑了单点近似下库仑相互作用的二阶自能。在计算的基础上，我们仔细研究了库仑相互作用对电导的影响作为桥的拉伸长度的函数。我们表明，在平台的电导值偏离的倍数的普遍值2 e2/h，并且随着温度的降低，偏差增加。这种温度依赖性随着库仑相互作用的强度而增加。此外，当子带边缘位于费米能量附近时，在平台之间出现谷。当库仑相互作用在高温下很弱时，或者当库仑...
Electron transport in an atom-sized bridge between a metal surface and a tip of a scanning tunneling microscope is investigated with the aid of the Hubbard Hamiltonian laying stress on the effects of the intrasite Coulomb interaction. The second-order self-energy with respect to the Coulomb interaction in a single-site approximation is taken into account in calculating the conductance of the bridge. On the basis of the calculation, we closely examine the effects of the Coulomb interaction on the conductance as a function of the stretching length of the bridge. We show that the conductance value at the plateau deviates from multiples of the universal value of 2e2/h, and that the deviation increases as the temperature is decreased. This temperature dependence increases with the strength of the Coulomb interaction. In addition, when the subband edge lies energetically near the Fermi energy, a valley appears between the plateaus. When the Coulomb interaction is weak at a high temperature, or when the Coulomb ...