Real-space titration and manipulation of particle-like correlated electrons in doped Mott insulator

Yanyan Geng; Haoyu Dong; Renhong Wang; Zilu Wang; Jianfeng Guo; Shuo Mi; Yan Li; Fei Pang; Rui Xu; Li Huang; Hong-Jun Gao; Wei Ji; Shancai Wang; Weichang Zhou; Zhihai Cheng

arXiv · 2507.05756

Real-space titration and manipulation of particle-like correlated electrons in doped Mott insulator

Yanyan Geng·Haoyu Dong·Renhong Wang·Zilu Wang·Jianfeng Guo·Shuo Mi·Yan Li·Fei Pang·Rui Xu·Li Huang·Hong-Jun Gao·Wei Ji·Shancai Wang·Weichang Zhou·Zhihai Cheng

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Abstract

The localized (particle-like) correlated electrons deserve particular attention as they govern various exotic quantum phenomena, such as quantum spin liquids, Wigner crystals, and Mott insulators in correlated systems. However, direct observation and manipulation of these particle-like electrons at the atomic or single-electron scale remain highly challenging. Here, we successfully realize and directly visualize particle-like correlated electrons in 1T-TaS2 through hole doping. The potential-dependent local electronic structure of single particle-like electron is revealed by angle-resolved photoemission spectroscopy (ARPES), scanning tunneling spectroscopy (STS) combined with theoretical calculations. The complex correlated interactions including nearest-neighbor attractive interactions and many-body repulsive interactions are further demonstrated and discussed based on the spatial distribution of particle-like electrons. Furthermore, the tentative manipulation of the particle-like electrons is successfully achieved by the energy-excitation mechanism. Our results not only provide profound insights into particle-like electrons in correlated systems, but also establish a versatile platform for designing and controlling quantum states at the atomic scale.

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Yanyan Geng, Haoyu Dong, Renhong Wang, Zilu Wang, Jianfeng Guo, Shuo Mi, Yan Li, Fei Pang, Rui Xu, Li Huang, Hong-Jun Gao, Wei Ji, Shancai Wang, Weichang Zhou, Zhihai Cheng. 2025-07-08. Real-space titration and manipulation of particle-like correlated electrons in doped Mott insulator. https://arxiv.org/abs/2507.05756

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