Resonant transport and electrostatic effects in single-molecule electrical junctions
Resonant transport and electrostatic effects in single-molecule electrical junctions
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DOI：
10.1103/physrevb.91.195438
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发表时间：
2015-05-26
影响因子：
3.7
通讯作者：
Nichols, Richard J.
中科院分区：
文献类型：
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作者：
Brooke, Carly;Vezzoli, Andrea;Nichols, Richard J.
在这篇文章中，我们证明了HS（CH 2）（n）[1，4-C6 H4]（CH 2）（n）SH（n = 1，3，4，6）金属-分子-金属结中的输运共振的结构控制，使用基于扫描隧道显微镜的I（z）方法制造和测试。Breit-Wigner共振起源于芳烃p-键合轨道之一，随着n的增加，该轨道变得尖锐并更接近接触费米能。因此，改变亚甲基的数目导致电导随分子长度的非常浅的衰减。我们证明，通过分析金属-分子界面处产生的静电平衡引起的影响，可以直接合理化这里观察到的电行为。这样的共振提供了未来的前景，在分子电子学控制电荷传输在较长的距离，也在单分子电导开关，如果共振可以外部门控。
In this contribution we demonstrate structural control over a transport resonance in HS(CH2)(n)[1,4 - C6H4](CH2)(n)SH (n = 1, 3, 4, 6) metal-molecule-metal junctions, fabricated and tested using the scanning tunneling microscopy-based I(z) method. The Breit-Wigner resonance originates from one of the arene p-bonding orbitals, which sharpens and moves closer to the contact Fermi energy as n increases. Varying the number of methylene groups thus leads to a very shallow decay of the conductance with the length of the molecule. We demonstrate that the electrical behavior observed here can be straightforwardly rationalized by analyzing the effects caused by the electrostatic balance created at the metal-molecule interface. Such resonances offer future prospects in molecular electronics in terms of controlling charge transport over longer distances, and also in single-molecule conductance switching if the resonances can be externally gated.