High-temperature bad-metal transport has been recently studied both theoretically and in experiments as one of the key signatures of strong electronic correlations. Here we use the dynamical mean field theory and its cluster extensions, as well as the finite-temperature Lanczos method to explore the influence of lattice frustration on the thermodynamic and transport properties of the Hubbard model at high temperatures. We consider the triangular and the square lattices at half-filling and at 15% hole doping. We find that for $T\gtrsim 1.5t$ the self-energy becomes practically local, while the finite-size effects become small at lattice size $4\times 4$ for both lattice types and doping levels. The vertex corrections to optical conductivity, which are significant on the square lattice even at high temperatures, contribute less on the triangular lattice. We find approximately linear temperature dependence of dc resistivity in doped Mott insulator for both types of lattices.

中文翻译：

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Hubbard模型中高温下的电荷传输：三角形与正方形晶格

作为强电子相关性的关键特征之一，高温重金属的输送最近已在理论上和实验中得到了研究。在这里，我们使用动力学平均场理论及其簇扩展，以及有限温度Lanczos方法来研究晶格受挫对高温下Hubbard模型的热力学和输运性质的影响。我们考虑在半填充和15％空穴掺杂时的三角形和正方形晶格。我们发现$Ť\gtrsim 1.5Ť$ 自能量实际上变为局部能量，而有限尺寸的效应在晶格尺寸下变小 $4\times 4$对于晶格类型和掺杂水平。对光导率的顶点校正即使在高温下也对正方形晶格很重要，对三角形晶格的影响较小。我们发现两种类型的晶格在掺杂的Mott绝缘子中的直流电阻率都近似呈线性温度依赖性。