Tang Jiulin, Wang Hao, Tang Xinghui, Zhang Yongjie, Zhang Chun
Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117551, Singapore.
Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China.
ACS Omega. 2025 Apr 9;10(15):15250-15255. doi: 10.1021/acsomega.4c11037. eCollection 2025 Apr 22.
At the nano- or molecular scale, electron transport is often governed by quantum effects, for which the symmetry of the system could become a key factor. In this work, by state-of-the-art first-principles modeling and simulation, we show that the structural symmetry plays a unique role in properties of electronic circuits made of CNT (5,5) electrodes and nickelocene (NiCp) molecules, resulting in unusual transport phenomena beyond the classical circuit theories. For a single NiCp molecule sandwiched between two CNT (5,5) electrodes, we find that the symmetry change caused by the rotation of one CNT electrode greatly affects the conductance of the device, which may have important implications for understanding the performances of CNT-based quantum devices. We further show that when two NiCp molecular resistors are connected in series, the conductance of the resulting series-NiCp circuit can be significantly higher than the single-NiCp device at certain biases, in which the structural symmetry of the circuit plays a critical role. These results provide new opportunities for the future design of molecular devices with novel functions.
在纳米或分子尺度上，电子传输通常受量子效应支配，而系统的对称性可能成为关键因素。在这项工作中，通过最先进的第一性原理建模和模拟，我们表明结构对称性在由碳纳米管（5,5）电极和二茂镍（NiCp）分子制成的电子电路特性中起着独特作用，从而导致超出经典电路理论的异常传输现象。对于夹在两个碳纳米管（5,5）电极之间的单个NiCp分子，我们发现一个碳纳米管电极旋转引起的对称性变化极大地影响了器件的电导，这对于理解基于碳纳米管的量子器件的性能可能具有重要意义。我们进一步表明，当两个NiCp分子电阻串联连接时，在某些偏压下，所得串联NiCp电路的电导可能明显高于单个NiCp器件，其中电路的结构对称性起着关键作用。这些结果为未来设计具有新颖功能的分子器件提供了新机会。
