发表机构
Istanbul Technical University（伊斯坦布尔技术大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究一维双原子链量子发射体的拓扑与集体辐射，通过非厄米SSH模型揭示亚辐射、超辐射及边缘态，并分析其远场辐射特性。
AI 中文摘要
我们研究了一维双原子链中相同量子发射体以交替间距排列并耦合到电磁真空时的拓扑和集体辐射性质。该系统实现了一个扩展的非厄米Su-Schrieffer-Heeger型模型，具有真空介导的长程相互作用和集体耗散。我们关注单激发子流形，其中动力学由有效哈密顿量描述。对于无限链，复能带结构揭示了与光线外波矢相关的亚辐射模式，以及实部能带交叉发生的参数区域。体拓扑由复Berry相位表征，在存在反演对称性和谱隙时该相位保持量子化。对于有限链，利用精确对角化，我们识别出具有不同衰减率和空间轮廓的超辐射、亚辐射和边缘态。当能量谱实部存在体隙时，边缘态出现在拓扑非平凡区域，而亚辐射态表现出强烈抑制的衰减且具有系统尺寸依赖性。最后，我们分析了与不同类别本征态相关的远场辐射模式，并表明发射特性反映了衰减性质、空间局域化以及晶胞振幅的奇偶性。
英文摘要
We investigate the topological and collective radiative properties of a one-dimensional diatomic chain of identical quantum emitters with alternating spacing, coupled to the electromagnetic vacuum. The system realizes an extended, non-Hermitian Su-Schrieffer-Heeger-type model with vacuum-mediated long-range interactions and collective dissipation. We focus on the single-excitation manifold, where the dynamics are described by an effective Hamiltonian. For an infinite chain, the complex band structure reveals subradiant modes associated with wave vectors outside the light line, as well as parameter regimes where real-part band crossings occur. The bulk topology is characterized by a complex Berry phase, which remains quantized in the presence of inversion symmetry and a spectral gap. For finite chains, using exact diagonalization, we identify superradiant, subradiant, and edge states with distinct decay rates and spatial profiles. Edge states emerge in the topologically nontrivial regime when a bulk gap in the real part of the energy spectrum is present, while subradiant states exhibit strongly suppressed decay with system-size dependence. Finally, we analyze the far-field radiation patterns associated with different classes of eigenstates and show that the emission characteristics reflect the decay properties, spatial localization, and the parity of the unit-cell amplitudes.
CommentsSubmitted to Physical Review A
