发表机构
University of Stuttgart; Ludwig Maximilian University of Munich（斯图加特大学; 慕尼黑路德维希-马克西米利安大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究通过iDMRG模拟揭示了对称阻塞模型中拓扑有序相到平凡顺磁相的连续相变，并证实了拓扑相的稳定性及磁通凝聚机制。
AI 中文摘要
我们提出了一个具有局部 $\mathbb{Z}_2$ 对称性的阻塞哈密顿量的数值研究。对于此类模型，在弱拉比驱动下，拓扑有序基态的存在性已被严格证明 [T. F. Maier 等人，PRX Quantum 6, 030340 (2025)]。然而，弱驱动之外的相图仍然是一个开放问题。我们在圆柱体上进行大规模无限尺寸密度矩阵重正化群（iDMRG）模拟，并绘制出该模型的完整相图。我们发现拓扑有序相与平凡顺磁相之间存在一个连续相变，并数值确认了拓扑有序相在拉比驱动达到系统特征能量尺度时的稳定性。此外，我们计算了激发能隙，并表明电荷能隙在相变过程中保持开放，且电荷在平凡相中被禁闭。另一方面，对称扇区中的能隙在相变处闭合，这与磁通激发的凝聚一致。
英文摘要
We present a numerical study of a blockade Hamiltonian with a local $\mathbb{Z}_2$ symmetry. For such models, the existence of a topologically ordered ground state has been proven rigorously for weak Rabi driving [T. F. Maier et al., PRX Quantum 6, 030340 (2025)]. However, the phase diagram beyond weak driving is still an open question. We perform large-scale infinite-size density matrix renormalization group (iDMRG) simulations on a cylinder and map out the full phase diagram of the model. We find a single continuous phase transition between the topologically ordered phase and a trivial paramagnetic phase, and confirm numerically the stability of the topologically ordered phase up to Rabi drives comparable to the characteristic energy scale of the system. Furthermore, we compute the excitation gaps and show that the charge gap remains open across the phase transition and charges become confined in the trivial phase. On the other hand, the gap in the symmetric sector closes at the transition, consistent with the condensation of flux excitations.
Comments14 pages, 6 figures
