The electron transport through single electron transistor (SET) consisting of quantum dot (QD) coupled to two metallic electrodes has been studied by employing the non-equilibrium Green function (NEGF) technique. The QD considered in this study has a single energy level and non-interacting electrons. The current-voltage characteristics of QD has been studied by using Meir-Wingreen expression. In this paper, an analytical approximation of Meir-Wingreen formula has been presented with respect to the following conditions: (1) low-temperature limit, (2) finite temperature limit with finite energy$\left|\epsilon -{\epsilon }_d\right|<kT$, (3) finite temperature limit with finite bias $\text{Γ}<e\left|V\right|/2<KT<{\epsilon }_d$, and at high temperatures. Furthermore, the derived analytical formulae are employed to investigate the effect of device parameters (energy level, tunneling rate “level width”, gate voltage, and temperature) on the current-voltage characteristic of SET.

已经通过采用非平衡格林函数（NEGF）技术研究了通过量子点（QD）耦合到两个金属电极的单电子晶体管（SET）的电子传输。本研究中考虑的量子点具有单一能级和不相互作用的电子。通过使用Meir-Wingreen表达式研究了QD的电流-电压特性。本文针对以下条件提出了Meir-Wingreen公式的解析近似：（1）低温极限，（2）有限能量的有限温度极限$\left|\epsilon -{\epsilon }_d\right|<ķŤ$，（3）具有有限偏差的有限温度极限 $\text{Γ}<Ë\left|V\right|/2<ķŤ<{\epsilon }_d$，并在高温下使用。此外，导出的分析公式用于研究器件参数（能级，隧穿速率“能级宽度”，栅极电压和温度）对SET电流-电压特性的影响。