阻挫团簇自旋链中宏观猫态与多通道纠缠的涌现
Emergence of a Macroscopic Cat State and Multi-Channel Entanglement in a Frustrated Cluster Spin Chain
浏览论文内容
中文总结 AI 辅助
本文研究结合团簇伊辛与各向异性次近邻伊辛模型的一维阻挫自旋链，证实其存在一级量子相变，铁磁相含宏观猫态，非公度相有四通道纠缠，还探讨了该系统在量子计量学中的应用价值与实验可行性。
中文摘要 AI 辅助
我们研究了一维阻挫自旋链，它结合了团簇伊辛（cluster-Ising）和各向异性次近邻伊辛模型。首先，我们从历史视角论证该研究模型的合理性。接着详细研究了两个量子相，证明它们被一级量子相变分隔：一侧基态对应铁磁相，存在宏观猫态，且有小能隙，在热力学极限下会闭合；另一侧，竞争相互作用阻止拓扑相形成，但保留大的非公度量子关联，我们证明其与简单顺磁根本不同，将其命名为非公度相，这是一个有能隙的相，其能隙在热力学极限下不闭合。铁磁相有两个主导的施密特系数，非公度相有四个，对应四个不同的二分纠缠通道对基态有显著贡献。最后，我们讨论了宏观猫态在量子计量学应用中的效用，以及该系统的实验可行性。
英文摘要
We study a one-dimensional frustrated spin chain, which combines cluster-Ising and anisotropic next-nearest neighbor Ising models. We first offer a historical perspective that justifies the studied model. Then we study in detail the two quantum phases and prove that they are separated by a first order quantum phase transition. On one side, the ground state corresponds to a ferromagnetic phase, shows the presence of macroscopic cat states, and a small gap that closes in the thermodynamic limit. On the other phase, competing interactions avoid the establishment of a topological phase, though it conserves large incommensurate quantum correlations. We prove it is fundamentally distinct from a simple paramagnet, and we name it an incommensurate phase. This is a gapped phase, which gap does not close in the thermodynamic limit. While in the ferromagnetic phase there are two dominant Schmidt coefficients, in the incommensurate phase there are four. This corresponds to four distinct bipartite entanglement channels contributing substantially to the ground state. Finally, we discuss the utility of the macroscopic cat states for quantum metrology applications and the experimental feasibility of the system.
