碱金属原子掺杂BDC60分子中整流特性第一性原理研究

First-Principles Study of the Rectifying Properties of the Alkali-Metal-Atom-Doped BDC60 Molecule

利用第一性密度泛函理论和非平衡格林函数相结合的方法,研究了碱金属原子掺杂对BDC60分子电子输运性质的影响.计算结果表明,在极低偏压下碱金属掺杂的BDC60分子能够表现出非常优良的整流性能,同时也展示出显著的负微分电阻行为.根据透射谱和前线分子轨道及其空间分布随外加偏压的变化等方面的分析,系统地讨论了整流以及负微分电阻行为产生的内在机理.我们的研究有助于BDC60分子在未来低偏压整流和负微分电阻分子器件中的应用.

We investigated the effect of alkali-metal-atom doping on the electronic transport properties of BDC60 molecules, using a combination of first-principles density-functional theory and the non-equilibrium Green＇s function. Our calculation results show that alkali-metal-atom-doped BDC60 molecules exhibit good rectifying and negative differential resistance behaviors at very low bias. The intrinsic mechanisms for these phenomena are discussed systematically in terms of the transmission spectra and frontier molecular orbitals, as well as their spatial distributions under various external applied biases. Our study will help in developing future applications of BDC60 molecules in low-bias rectifying and negative differential resistance molecular devices.