论文标题
图形蒙特卡洛方法用于具有一般相互作用和杂交的杂质模型
Diagrammatic Monte Carlo Method for Impurity Models with General Interactions and Hybridizations
论文作者
论文摘要
我们提出了一种图形蒙特卡洛方法，用于与一般相互作用和一般杂交功能的量子杂质问题。我们的方法使用递归决定因素方案来散射幅度的样品图。与其他一般杂质问题的方法不同，不需要通过有限数量的浴缸状态对连续杂交函数进行近似，并且访问低温不会产生指数成本。我们测试了分子系统示例的方法，在该方法中，我们系统地变化了温度，原子间距离和基集尺寸。我们进一步将方法应用于通过嵌入相关抗铁磁NIO的自我能力嵌入计算产生的杂质问题。我们发现该方法是大量轨道的量子杂质问题的理想选择，但仅适度相关性。
We present a diagrammatic Monte Carlo method for quantum impurity problems with general interactions and general hybridization functions. Our method uses a recursive determinant scheme to sample diagrams for the scattering amplitude. Unlike in other methods for general impurity problems, an approximation of the continuous hybridization function by a finite number of bath states is not needed, and accessing low temperature does not incur an exponential cost. We test the method for the example of molecular systems, where we systematically vary temperature, interatomic distance, and basis set size. We further apply the method to an impurity problem generated by a self-energy embedding calculation of correlated antiferromagnetic NiO. We find that the method is ideal for quantum impurity problems with a large number of orbitals but only moderate correlations.
