Institut für Physik, BTU Cottbus, Germany.
Phys Rev Lett. 2011 Aug 12;107(7):076402. doi: 10.1103/PhysRevLett.107.076402. Epub 2011 Aug 9.
Based on the variational Gutzwiller theory, we present a method for the computation of response functions for multiband Hubbard models with general local Coulomb interactions. The improvement over the conventional random-phase approximation is exemplified for an infinite-dimensional two-band Hubbard model where the incorporation of the local multiplet structure leads to a much larger sensitivity of ferromagnetism on the Hund coupling. Our method can be implemented into local-density approximation and Gutzwiller schemes and will therefore be an important tool for the computation of response functions for strongly correlated materials.
基于变分 Gutzwiller 理论，我们提出了一种计算具有一般局域库仑相互作用的多带 Hubbard 模型的响应函数的方法。与传统的随机相位近似相比，我们通过在无限维双带 Hubbard 模型中加入局域多体结构，提高了对铁磁性的 Hund 耦合的灵敏度。我们的方法可以应用于局域密度近似和 Gutzwiller 方案，因此它将成为计算强关联材料响应函数的重要工具。
