论文标题
相互作用扩展Inch虫蒙特卡洛求解器用于晶格和杂质模型
Interaction expansion inchworm Monte Carlo solver for lattice and impurity models
论文作者
论文摘要
具有一般相互作用和杂交项的多轨量子杂质模型出现在广泛的应用中，包括嵌入，量子传输和纳米科学。但是，大多数量子杂质求解器仅限于一些杂质轨道，离散的浴室，对角杂交或密度密度相互作用。在这里，我们将Inch虫量子蒙特卡洛方法推广到相互作用的扩展中，并探索其在杂质和晶格模型研究中遇到的典型单一和多轨问题中的应用。我们的实现通常优于相互作用扩展中裸露和粗体的量子蒙特卡洛算法。到目前为止，对于这里研究的系统，它仍然不如更专业的杂交扩展和辅助场算法。在Inch Norm Monte Carlo中没有遇到与非物理固定点的收敛问题，这种问题阻碍了所谓的大胆方法。
Multi-orbital quantum impurity models with general interaction and hybridization terms appear in a wide range of applications including embedding, quantum transport, and nanoscience. However, most quantum impurity solvers are restricted to a few impurity orbitals, discretized baths, diagonal hybridizations, or density-density interactions. Here, we generalize the inchworm quantum Monte Carlo method to the interaction expansion and explore its application to typical single- and multi-orbital problems encountered in investigations of impurity and lattice models. Our implementation generically outperforms bare and bold-line quantum Monte Carlo algorithms in the interaction expansion. So far, for the systems studied here, it remains inferior to the more specialized hybridization expansion and auxiliary field algorithms. The problem of convergence to unphysical fixed points, which hampers so-called bold-line methods, is not encountered in inchworm Monte Carlo.
