Abstract We show an implementation of density matrix embedding theory (DMET) for the spin lattice of infinite size. It is indeed a special form of hierarchical mean-field (HMF) theory. In the method, we divide the lattice into a small part and a large part. View the small part as an impurity, embedding in the large part, which is viewed as the environment. We deal the impurity with a high accuracy method. But treat the environment with a low-level method: the states of the environment nearby the impurity are expressed by a set of multiple block product states, while the distant parts are treated by mean-field consideration. Our method allows for the computation of the ground state of the infinite two-dimensional quantum spin systems. In the text, we take the frustrated Heisenberg model as an example to test our method. The ground state energy we calculated can reach a high accuracy. We also calculate the magnetization, and the fidelity to study the quantum phase transitions.

中文翻译：

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使用分层平均场方法实现密度矩阵嵌入理论

摘要 我们展示了无限尺寸自旋晶格的密度矩阵嵌入理论 (DMET) 的实现。它确实是分层平均场（HMF）理论的一种特殊形式。在该方法中，我们将格子分为一小部分和一大部分。将小部分视为杂质，嵌入被视为环境的大部分中。我们用高精度的方法处理杂质。但是用一种低级的方法处理环境：杂质附近的环境状态用一组多个块积状态表示，而远处的部分则用平均场考虑处理。我们的方法允许计算无限二维量子自旋系统的基态。在文中，我们以受挫的海森堡模型为例来测试我们的方法。我们计算的基态能量可以达到很高的精度。我们还计算了磁化强度，以及研究量子相变的保真度。