Room-Temperature Quantum Interference in Perovskite Quantum Dot Junctions
Authors: Haining Zheng, Songjun Hou, Chengguang Xin, Qingqing Wu, Feng Jiang, Zhibing Tan, Xin Zhou, Luchun Lin, Wenxiang He, Qingmin Li, Jueting Zheng, Longyi Zhang, Junyang Liu, Yang Yang, Jia Shi, Xiaodan Zhang, Ying Zhao, Yuelong Li*, Colin Lambert*, Wenjing Hong*
The studies of quantum interference effects through bulk perovskite materials at the Ångstrom scale still remain as a major challenge. Herein, we provide the observation of room-temperature quantum interference effects in metal halide perovskite quantum dots (QDs) using the mechanically controllable break junction technique. Single-QD conductance measurements reveal that there are multiple conductance peaks for the CH3NH3PbBr3 and CH3NH3PbBr2.15Cl0.85QDs, whose displacement distributions match the lattice constant of QDs, suggesting that the gold electrodes slide through different lattice sites of the QD via Au-halogen coupling. We also observe a distinct conductance ‘jump’ at the end of the sliding process, which is further evidence that quantum interference effects dominate charge transport in these single-QD junctions. This conductance ‘jump’ is also confirmed by our theoretical calculations utilizing density functional theory combined with quantum transport theory. Our measurements and theory create a pathway to exploit quantum interference effects in quantum-controlled perovskite materials.