College of Physics and Electronic Engineering, Sichuan Normal University, Chengdu, China.
Phys Chem Chem Phys. 2023 May 17;25(19):13265-13274. doi: 10.1039/d2cp05677a.
Inspired by the requirements of miniaturization and multifunction of molecular devices, we investigate the quantum transport properties of three unique molecular devices with silicon carbide chains bridging gold electrodes by an approach. The pronounced quantum effects, including the oscillation of charge, conductance, and current, together with the negative differential resistance (NDR), have been observed simultaneously over a wide region in the double-chain device. It changes the regular situation that these two effects usually emerge in single-chain systems at the same time. Inspections of the visible differences in the transport behaviors relevant to length and bias between the three devices further evidence that the interchain interaction and molecule-electrode coupling are decisive factors for achieving the quantum effects of oscillation and NDR. These two factors can improve electronic transport capability through enhancing transmission, strengthening the delocalization of frontier molecular orbitals, and reducing potential barriers. Our results not only lay a solid foundation for the application of silicon carbide chains in the miniaturized and multifunctional molecular devices with good performance, but also provide an efficient way to the continuing search for materials with multiple controllable quantum effects in nanoelectronics.
受分子器件小型化和多功能化要求的启发,我们通过 方法研究了三种具有独特结构的分子器件的量子输运性质,该分子器件由碳化硅链桥接金电极。在双链器件中,我们在很宽的范围内同时观察到了显著的量子效应,包括电荷、电导和电流的振荡以及负微分电阻(NDR)。这改变了这两种效应通常在单链系统中同时出现的常规情况。对三个器件中与长度和偏置相关的输运行为的明显差异的检查进一步证明,链间相互作用和分子-电极耦合是实现振荡和 NDR 量子效应的决定性因素。这两个因素可以通过增强传输、增强前沿分子轨道的离域和降低势垒来提高电子传输能力。我们的研究结果不仅为碳化硅链在具有良好性能的小型化和多功能分子器件中的应用奠定了坚实的基础,而且为在纳米电子学中继续寻找具有多种可控量子效应的材料提供了一种有效的方法。