Supersymmetric multicritical point in a model of lattice fermions
Supersymmetric multicritical point in a model of lattice fermions
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DOI：
10.1103/physrevb.87.165145
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发表时间：
2013-04-30
影响因子：
3.7
通讯作者：
Schoutens, Kareljan
中科院分区：
文献类型：
--
作者：
Bauer, Bela;Huijse, Liza;Schoutens, Kareljan
研究了一种具有无限大近邻斥力的无自旋费米子模型，该模型具有微观超对称性。据推测，在连续介质中，模型用中心电荷c = 3/2的超共形极小模型来描述。到目前为止，由于数值数据的有限大小修正，还不可能证实这一猜想。我们将这些修正的起源追溯到不寻常的边缘算子的存在，这些算子打破了洛伦兹不变性，但保留了部分超对称性。通过主要依赖于密度矩阵重整化群的纠缠熵计算，我们能够显着减少有限大小的影响。这使我们能够明确地确定模型的连续统理论。我们还研究了模型的摄动，并证明了超对称模型是一个多临界点。我们的工作强调了纠缠熵作为量子多体系统相探测的力量。
We study a model of spinless fermions with infinite nearest-neighbor repulsion on the square ladder, which has microscopic supersymmetry. It has been conjectured that in the continuum, the model is described by the superconformal minimal model with central charge c = 3/2. Thus far, it has not been possible to confirm this conjecture due to strong finite-size corrections in numerical data. We trace the origin of these corrections to the presence of unusual marginal operators that break Lorentz invariance but preserve part of the supersymmetry. By relying mostly on entanglement entropy calculations with the density-matrix renormalization group, we are able to reduce finite-size effects significantly. This allows us to unambiguously determine the continuum theory of the model. We also study perturbations of the model and establish that the supersymmetric model is a multicritical point. Our work underlines the power of entanglement entropy as a probe of the phases of quantum many-body systems.