论文标题
2D哈伯德模型中的自旋扩散和自旋电导率
Spin diffusion and spin conductivity in the 2d Hubbard model
论文作者
论文摘要
我们通过使用有限的温度Lanczos方法研究了方格Hubbard模型中的自旋扩散和自旋电导率。我们表明，自旋扩散与电荷扩散的行为不同，并且具有非单调$ t $依赖性。这是由于逐渐解放了电荷，这导致了旋转运输，并在海森堡交换时在低温下的活跃中增强了电荷。我们进一步表明，远离半填充和零磁化会增加自旋扩散，但增加不足以调和模型计算与冷原子的最新测量之间的差异。
We study the spin diffusion and spin conductivity in the square lattice Hubbard model by using the finite-temperature Lanczos method. We show that the spin diffusion behaves differently from the charge diffusion and has a nonmonotonic $T$ dependence. This is due to a progressive liberation of charges that contribute to spin transport and enhance it beyond that active at low temperature due to the Heisenberg exchange. We further show that going away from half-filling and zero magnetization increases the spin diffusion, but that the increase is insufficient to reconcile the difference between the model calculations and the recent measurements on cold-atoms.
