The Nature of Transport Variations in Molecular Heterojunction Electronics
The Nature of Transport Variations in Molecular Heterojunction Electronics
复制标题
DOI：
10.1021/nl9013875
复制
发表时间：
2009-10-01
期刊：
影响因子：
10.8
通讯作者：
Segalman, Rachel A.
中科院分区：
文献类型：
--
作者：
Malen, Jonathan A.;Doak, Peter;Segalman, Rachel A.
通过测量一系列金属-分子金属结的热电势，量化了它们的输运涨落和变化。选择了不同长度和自由度的硫醇结合芳香族分子来了解变化的大小和来源。结热功率是通过测量在不同温度下保持的两个金触点之间捕获的分子之间的电压差来确定的。虽然任何给定的测量都是非常稳定的，但重复测量的分布宽度意味着最高占据分子轨道(HOMO)相对于接触的费米能量的偏移量的变化，在大小上类似于标称偏移量本身。对数据的统计分析表明，这些变化产生于结点形成处，随着分子长度的增加而增加，并由接触几何和轨道杂化以及分子间相互作用的变化所主导。
Transport fluctuations and variations in a series of metal-molecule metal junctions were quantified through measurements of their thermopower. Thiol bound aromatic molecules of various lengths and degrees of freedom were chosen to understand the magnitude and origins of the variations. Junction thermopower was determined by measuring the voltage difference across molecules trapped between two gold contacts hold at different temperatures. While any given measurement was remarkably stable, the breadth of distributions from repeated measurements Implies variations in the offset of the highest occupied molecular orbital (HOMO) relative to the Fermi Energy of the contacts, similar In magnitude to the nominal offset Itself. Statistical analysis of data shows that these variations are born at the Junction formation, Increase with molecular length, and are dominated by variations in contact geometry and orbital hybridization, as well as intermolecular interactions.