Jia Chunxia, Cao Liemao, Zhou Xiaoying, Zhou Benliang, Zhou Guanghui
Department of Physics, Key Laboratory for Low-Dimensional Structures and Quantum Manipulation (Ministry of Education), and Synergetic Innovation Center for Quantum Effects and Applications of Hunan, Hunan Normal University, Changsha 410081, People's Republic of China. Institute of Modern Physics and Department of Physics, Hunan University of Science and Technology, Xiangtan 411201, People's Republic of China.
J Phys Condens Matter. 2018 Jul 4;30(26):265301. doi: 10.1088/1361-648X/aac4ff. Epub 2018 May 15.
We study the electron transport properties through the junction of a benzene molecule in conjunction with two monolayer zigzag-edged phosphorene nanoribbon (ZPNR) electrodes by applying the nonequilibrium Green's functions in combination with the density functional theory. We find that the molecular junction with two phosphorus-carbon bonds exhibits an interesting low-bias negative differential resistance effect with a peak-to-valley ratio of 29, which originates from the edge states in ZPNR due to the anisotropic band structure of phosphorene. Importantly, the performance of the junction can be tuned via the molecule-ZPNR interface bonding. The findings may be useful in sensitive-device applications. Furthermore, the physical mechanisms are revealed and discussed in terms of the electronic transmission spectrum, the evolution of the frontier molecular orbitals, the local device density of states around the Fermi level, and the projected density of states.
我们通过结合非平衡格林函数和密度泛函理论，研究了苯分子与两个单层锯齿形边缘磷烯纳米带（ZPNR）电极形成的结的电子输运性质。我们发现，具有两个磷-碳键的分子结表现出有趣的低偏置负微分电阻效应，峰谷比为29，这源于磷烯的各向异性能带结构导致的ZPNR中的边缘态。重要的是，结的性能可以通过分子-ZPNR界面键合来调节。这些发现可能对敏感器件应用有用。此外，从电子传输光谱、前沿分子轨道的演化、费米能级附近的局部器件态密度以及投影态密度等方面揭示并讨论了物理机制。
