Bai, Jie and Daaoub, Abdalghani and Sangtarash, Sara and Li, Xiaohui and Tang, Yongxiang and Zou, Qi and Sadeghi, Hatef and Liu, Shuai and Huang, Xiaojuan and Tan, Zhibing and Liu, Junyang and Yang, Yang and Shi, Jia and Mészáros, Gabor and Chen, Wenbo and Lambert, Colin and Hong, Wenjing (2019) Anti-resonance features of destructive quantum interference in single-molecule thiophene junctions achieved by electrochemical gating. Nature Materials, 18. pp. 364-369. ISSN 1476-1122
ECQI_Main_NMATER_Clean_20181114.pdf - Accepted Version
Download (1MB)
Abstract
Controlling the electrical conductance and in particular the occurrence of quantum interference in single-molecule junctions through gating effects has potential for the realization of high-performance functional molecular devices. In this work we used an electrochemically gated, mechanically controllable break junction technique to tune the electronic behaviour of thiophene-based molecular junctions that show destructive quantum interference features. By varying the voltage applied to the electrochemical gate at room temperature, we reached a conductance minimum that provides direct evidence of charge transport controlled by an anti-resonance arising from destructive quantum interference. Our molecular system enables conductance tuning close to two orders of magnitude within the non-faradaic potential region, which is significantly higher than that achieved with molecules not showing destructive quantum interference. Our experimental results, interpreted using quantum transport theory, demonstrate that electrochemical gating is a promising strategy for obtaining improved in situ control over the electrical performance of interference-based molecular devices. © 2019, The Author(s), under exclusive licence to Springer Nature Limited.