Intricately Entangled Spin and Charge Diffusion and the Coherence-Incoherence Crossover in the High-Dimensional Hubbard Model

Motivated by recent experimental studies thatinvestigate the evolution of dynamical spin and charge responses, we analyze the spin and chargediffusion spectra in both half-filled and doped one-band Hubbard model using Dynamical MeanField Theory (DMFT) combined with the Numerical Renormalization Group (NRG). We comparethe relative strengths and limitations of Density Matrix NRG (DMNRG) and Full Density MatrixNRG (FDM-NRG) in capturing low-frequency spectral features and their evolution with tempera-ture, interaction strength and band-filling.

受近期针对动态自旋与电荷响应演化的实验研究启发，我们采用结合数值重整化群（Numerical Renormalization Group, NRG）的动态平均场理论（Dynamical Mean Field Theory, DMFT），对半填充及掺杂单带哈伯德模型中的自旋与电荷扩散谱展开分析。我们对比了密度矩阵数值重整化群（Density Matrix NRG, DMNRG）与全密度矩阵数值重整化群（Full Density Matrix NRG, FDM-NRG）在捕捉低频光谱特征，以及这些特征随温度、相互作用强度与能带填充率演化情况时的相对优势与局限性。