发表机构
School of Physical Science and Engineering, Tongji University（同济大学物理科学与工程学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究证明一维费米-哈伯德模型中自旋轨道耦合可将排斥束缚双子驱动至连续谱，部分形成多体束缚态（BIC），并通过声学腔实验验证，深化了对相互作用束缚对连续谱物理的理解。
AI 中文摘要
排斥束缚的双子（doublons）是由强相互作用形成的双粒子复合体，通常与散射连续谱分离。引入自旋轨道耦合从根本上改变了底层能带结构，为将这些孤立对移向连续谱提供了强大的调节旋钮。然而，由于进入这种区域通常意味着立即解离，这种耦合能否在保持其束缚性质的同时将这些对驱动到连续谱内部，构成一个基本且未解决的挑战。在这里，我们展示了一维费米-哈伯德模型中的自旋轨道耦合可以将双子驱动到双粒子散射连续谱中。这些态中的大多数与扩展通道杂化并衰变，而一个子集保持解耦且空间束缚，形成多体连续谱束缚态（BICs）。我们将相互作用的双粒子问题映射到耦合声学腔的二维晶格上，并实验观察了辐射双子连续谱和受限的BIC态。这些结果表明，自旋轨道耦合可以将选定的双子转变为相互作用诱导的BIC，加深了对相互作用束缚对的连续谱物理的理解。
英文摘要
Repulsively bound doublons are two-particle composites formed by strong interactions and are usually separated from the scattering continuum. Introducing spin-orbit coupling fundamentally alters the underlying band structure, providing a powerful tuning knob to shift these isolated pairs toward this continuum. However, because entering such a regime typically dictates immediate dissociation, whether this coupling can drive these pairs inside while preserving their bound nature constitutes a fundamental unresolved challenge. Here we show that spin-orbit coupling in the one-dimensional Fermi-Hubbard model can drive doublons into the two-particle scattering continuum. Most of these states hybridize with extended channels and decay, whereas a subset remains decoupled and spatially bound, forming many-body bound states in the continuum (BICs). We map the interacting two-particle problem onto a two-dimensional lattice of coupled acoustic cavities, and experimentally observe both the radiating doublon continuum and the confined BIC states. These results demonstrate that spin-orbit coupling can turn selected doublons into interaction-induced BICs, deepening the understanding of continuum physics for interaction-bound pairs.
