Tang Chun, Huang Longfeng, Sangtarash Sara, Noori Mohammed, Sadeghi Hatef, Xia Haiping, Hong Wenjing
State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
Department of Chemistry, Shenzhen Grubbs Institute, Southern University of Science and Technology, Shenzhen 518055, China.
J Am Chem Soc. 2021 Jun 30;143(25):9385-9392. doi: 10.1021/jacs.1c00928. Epub 2021 Jun 18.
Quantum interference (QI) plays an imperative role in the operation of molecular devices within the phase-coherent length, and it is vital to harness the patterns of QI, i.e., constructive and destructive interference. However, the size of the single-molecule device is too small compared to most gate electrodes. Those gates act like a backgate to affect the molecular component uniformly. Switching the patterns of QI in the same molecular skeleton remains challenging. Here, we develop the atomically precise gating strategy that manipulates the frontier orbitals of molecular components, achieving the complete switching of QI patterns between destructive to constructive QI and leading to a significant conductance modulation at room temperature. The chemical gating effect is exerted locally on the pyridine nitrogen through the selective interaction to cationic reagents, with which we can also control the switching reversibility as desired. We demonstrate the unique effect of atomically precise gating to modulate the quantum interference at the single-molecule scale, opening an avenue to develop new-conceptual electronic devices.
量子干涉（QI）在相干长度范围内的分子器件运行中起着至关重要的作用，利用量子干涉的模式，即相长干涉和相消干涉，至关重要。然而，与大多数栅电极相比，单分子器件的尺寸太小。那些栅极起到背栅的作用，均匀地影响分子组件。在同一分子骨架中切换量子干涉模式仍然具有挑战性。在这里，我们开发了原子精确的门控策略，该策略操纵分子组件的前沿轨道，实现了量子干涉模式从相消干涉到相长干涉的完全切换，并在室温下导致显著的电导调制。通过与阳离子试剂的选择性相互作用，化学门控效应局部作用于吡啶氮上，利用这一点我们还可以根据需要控制切换的可逆性。我们展示了原子精确门控在单分子尺度上调制量子干涉的独特效果，为开发新概念电子器件开辟了一条途径。
