Quantum interference can deeply alter the nature of many-body phases of matter¹. In the case of the Hubbard model, Nagaoka proved that introducing a single itinerant charge can transform a paramagnetic insulator into a ferromagnet through path interference^2,3,4. However, a microscopic observation of this kinetic magnetism induced by individually imaged dopants has been so far elusive. Here we demonstrate the emergence of Nagaoka polarons in a Hubbard system realized with strongly interacting fermions in a triangular optical lattice^5,6. Using quantum gas microscopy, we image these polarons as extended ferromagnetic bubbles around particle dopants arising from the local interplay of coherent dopant motion and spin exchange. By contrast, kinetic frustration due to the triangular geometry promotes antiferromagnetic polarons around hole dopants⁷. Our work augurs the exploration of exotic quantum phases driven by charge motion in strongly correlated systems and over sizes that are challenging for numerical simulation^8,9,10.

量子干涉可以深刻改变物质多体相的性质¹。在 Hubbard 模型中，Nagaoka 证明引入单个巡回电荷可以通过路径干扰将顺磁绝缘体转变为铁磁体^2,3,4。然而，迄今为止，对这种由单独成像的掺杂剂引起的动磁力的微观观察还难以实现。在这里，我们展示了哈伯德系统中长冈极化子的出现，该系统通过三角形光学晶格中的强相互作用费米子实现^5,6。使用量子气体显微镜，我们将这些极化子成像为粒子掺杂剂周围延伸的铁磁气泡，这些气泡是由相干掺杂剂运动和自旋交换的局部相互作用产生的。相反，由于三角形几何形状引起的动力学挫败促进了空穴掺杂剂⁷周围的反铁磁极化子。我们的工作预示着在强相关系统中探索由电荷运动驱动的奇异量子相，并且其尺寸对数值模拟来说具有挑战性^8,9,10。