论文标题
仅基于偏置温度下的低偏置隧道电导，估计分子连接中的分子数量
Estimating the Number of Molecules in Molecular Junctions Merely Based on the Low Bias Tunneling Conductance at Variable Temperature
论文作者
论文摘要
Temperature ($T$) dependent conductance $G = G(T)$ data measured in molecular junctions are routinely taken as evidence for a two-step hopping mechanism.本文强调不一定是这种情况。 $ \ ln g $的曲线与$ 1/t $几乎线性（类似于Arrhenius的制度）的曲线最终转换为几乎水平的高原（Sommerfeld政权），或者由于$ 1/T $的增加，坡度逐渐降低，与单台式隧道机制完全兼容。 $ g $对$ t $的依赖性的结果包括分析精确和准确的近似公式和数值模拟。这些理论上的结果是一般的，从某种意义上说，它们不受限制，例如（单分子电移移（集合）或大面积）制造平台，仅选择用于分析所需的可用实验数据而被选择用于示例。要具体而言，我们详细检查了基于二代期（FC）的分子连接的传输测量。作为一个特别重要的发现，我们展示了如何利用$ g = g = g（t）$的当前分析公式来计算比率$ f = a _ {\ text {eff}} / a_n $之间的基于Egain顶部电极的大面积和标称区域之间的有效区域和标称区域之间。对于相关的大面积分子连接，我们对$ f \ times 10^{ - 4} $的估计与先前报道的值\ ib {基于完全不同的方法}相当。
Temperature ($T$) dependent conductance $G = G(T)$ data measured in molecular junctions are routinely taken as evidence for a two-step hopping mechanism. The present paper emphasizes that this is not necessarily the case. A curve of $\ln G$ versus $1/T$ decreasing almost linearly (Arrhenius-like regime) and eventually switching to a nearly horizontal plateau (Sommerfeld regime), or possessing a slope gradually decreasing with increasing $1/T$ is fully compatible with a single-step tunneling mechanism. The results for the dependence of $G$ on $T$ presented include both analytical exact and accurate approximate formulas and numerical simulations. These theoretical results are general, also in the sense that they are not limited, e.g., to the (single molecule electromigrated (SET) or large area EGaIn) fabrication platforms, which are chosen for exemplification merely in view of the available experimental data needed for analysis. To be specific, we examine in detail transport measurements for molecular junctions based on ferrocene (Fc). As a particularly important finding, we show how the present analytic formulas for $G=G(T)$ can be utilized to compute the ratio $f = A_{\text{eff}} / A_n$ between the effective and nominal areas of large area Fc-based junctions with an EGaIn top electrode. Our estimate of $f\approx 0.6 \times 10^{-4}$ is comparable with previously reported values \ib{based on completely different methods} for related large area molecular junctions.
