论文标题
在高温下，哈伯德模型中的电荷传输：三角形与方格
Charge transport in the Hubbard model at high temperatures: triangular versus square lattice
论文作者
论文摘要
最近在理论上还是在实验中研究了高温不良金属运输，这是强电子相关性的关键特征之一。在这里，我们使用动力学平均场理论（DMFT）及其簇扩展，以及有限温度的兰科斯方法（FTLM）来探索在高温下Hubbard模型的热力学和运输特性的晶格挫败感的影响。我们将三角形和正方形晶格在半填充和15 \％孔掺杂时考虑。我们发现，对于$ t \ gtrsim 1.5t $，自我能源实际上是本地的，而有限尺寸的效果在晶格大小的$ 4 \ times $ 4 $ 4 $中变小，用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，对于平方晶格也很重要，对三角形晶格的贡献较小。我们发现两种类型的晶格中掺杂的Mott绝缘子中直流电阻率的线性温度依赖性大致。
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 (DMFT) and its cluster extensions, as well as the finite-temperature Lanczos method (FTLM) 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 lattice 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.
