论文标题
纠缠光谱作为相互作用的无旋转费用模型的密度嵌入理论中相变的标记
Entanglement spectrum as a marker for phase transitions in the density embedding theory for interacting spinless fermionic models
论文作者
论文摘要
纠缠相关的特性可作为量子多体波函数的不错的指纹。但是，费米金模型的模型很难用标准数值方法进行评估，因为它们遭受了有限的尺寸效应。我们表明，所谓的密度嵌入理论（DET）可以与大尺寸密度矩阵重新归一化组分析获得的尺寸缩放分析相对高的尺寸缩放分析而对其进行评估。该方法将大规模的原始多体哈密顿量投射到本地群集上定义的少量基集，并通过调整局部密度矩阵来优化这些基础的选择。一维相互作用费米的Det纠缠光谱完美地再现了确切的纠缠谱，并作为相换点的标记。进一步表明，二维中的相变可以通过反映波函数结构变化的纠缠熵和忠诚度来确定。
Entanglement related properties work as nice fingerprint of the quantum many-body wave function. However, those of fermionic models are hard to evaluate in standard numerical methods because they suffer from finite size effects. We show that a so-called density embedding theory (DET) can evaluate them without size scaling analysis in comparably high quality with those obtained by the large-size density matrix renormalization group analysis. This method projects the large scale original many-body Hamiltonian to the small number of basis sets defined on a local cluster, and optimizes the choice of these bases by tuning the local density matrix. The DET entanglement spectrum of one-dimensional interacting fermions perfectly reproduces the exact ones and works as a marker of the phase transition point. It is further shown that the phase transitions in two-dimension could be determined by the entanglement entropy and the fidelity that reflects the change of the structure of the wave function.
