We apply the density-matrix renormalization group (DMRG) method to a one-dimensional Hubbard model that lacks Umklapp scattering and thus provides an ideal case to study the Mott-Hubbard transition analytically and numerically. The model has a linear dispersion and displays a metal-to-insulator transition when the Hubbard interaction~$U$ equals the band width, $U_{\rm c}=W$, where the single-particle gap opens linearly, $Δ(U\geq W)=U-W$. The simple nature of the elementary excitations permits to determine numerically with high accuracy the critical interaction strength and the gap function in the thermodynamic limit. The jump discontinuity of the momentum distribution $n_k$ at the Fermi wave number $k_{\rm F}=0$ cannot be used to locate accurately $U_{\rm c}$ from finite-size systems. However, the slope of $n_k$ at the band edges, $k_{\rm B}=\pm π$, reveals the formation of a single-particle bound state which can be used to determine $U_{\rm c}$ reliably from $n_k$ using accurate finite-size data.
The Mott metal-insulator transition is a typical strong correlation effect triggered by the Umklapp scattering. However, in a physical system, the Umklapp scattering coexists with the normal scattering, including both forward and backward scattering, which conserves the total momentum of scattered electrons. Therefore, it is not easy to quantify the contribution of the Umklapp scattering in a Mott metal-insulator transition. To resolve this difficulty, we propose to explore these scattering processes separately. We study the contribution of each scattering process in the one-dimensional Hubbar…
Evidence of Mott Insulator with Thermally Induced Melting Behavior in Kagome Compound Nb3Cl8
International Center for Quantum Materials, School of Physics, Peking University（北京大学物理学院量子材料国际中心）；Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology（北京理工大学物理学院先进光电量子结构测量教育部重点实验室量子物理中心）；Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所凝聚态物理国家实验室）；Research Center for Electronic and Optical Materials, National Institute of Material Sciences（国立材料科学研究所电子与光学材料研究中心）；Research Center for Materials Nanoarchitectonics, National Institute of Material Sciences（国立材料科学研究所材料纳米构造研究中心）；School of Materials Science and Engineering, Peking University（北京大学材料科学与工程学院）；State Key Laboratory for Mesoscopic Physics, Frontiers Science Centre for Nano-optoelectronics, School of Physics, Peking University（北京大学物理学院介观物理国家重点实验室纳米光电子前沿科学中心）；Collaborative Innovation Center of Quantum Matter（量子物质协同创新中心）
Interlayer Coupling Driven Correlated and Charge-Ordered Electronic States in a Transition Metal Dichalcogenide Superlattice
Wuhan University（武汉大学）；Hubei University（湖北大学）；Hunan University（湖南大学）；ShanghaiTech University（上海科技大学）；University of Oxford（牛津大学）；Institute of Physics, Chinese Academy of Science（中国科学院物理研究所）；Nanjing University（南京大学）；Wuhan Institute of Quantum Technology（武汉量子技术研究院）
