Motivated by the recent measurements of the spatial distribution of single particle excitation states in a hole-doped Mott insulator,we study the effects of impurity on the in-gap states,induced by the doped holes,in the Hubbard model on the square lattice by the cluster perturbation theory.We find that a repulsive impurity potential can move the in-gap state from the lower Hubbard band towards the upper Hubbard band,providing a good account for the experimental observation.The distribution of the spectral function in the momentum space can be used to discriminate the in-gap state induced by doped holes and that by the impurity.The spatial characters of the in-gap states in the presence of two impurities are also discussed and compared to the experiment.

Cheng-Ping He;Shun-Li Yu;Tao Xiang;Jian-Xin Li

National Laboratory of Solid State Microstructures and School of Physics,Nanjing University,Nanjing 210093,China;Collaborative Innovation Center of Advanced Microstructures,Nanjing University,Nanjing 210093,China;Institute of Physics,National Laboratory for Condensed Matter Physics,Chinese Academy of Sciences,Beijing 100190,China;Department of Physics,University of Chinese Academy of Sciences,Beijing 100190,China;Beijing Academy of Quantum Information Sciences,Beijing 100193,China

中国物理快报（英文版）

[1]Cheng-Ping He;Shun-Li Yu;Tao Xiang;Jian-Xin Li-.Effect of Impurity on the Doping-Induced in-Gap States in a Mott Insulator)[J].中国物理快报（英文版）,2022(05):139-145

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