The iron-chalcogenide high temperature superconductor Fe(Se,Te) (FST) has been reported to exhibit complex magnetic ordering and nontrivial band topology which may lead to novel superconducting phenomena. However, the recent studies have so far been largely concentrated on its band and spin structures while its mesoscopic electronic and magnetic response, crucial for future device applications, has not been explored experimentally. Here, we used scanning superconducting quantum interference device microscopy for its sensitivity to both local diamagnetic susceptibility and current distribution in order to image the superfluid density and supercurrent in FST. We found that in FST with 10% interstitial Fe, whose magnetic structure was heavily disrupted, bulk superconductivity was significantly suppressed whereas edge still preserved strong superconducting diamagnetism. The edge dominantly carried supercurrent despite of a very long magnetic penetration depth. The temperature dependence of the superfluid density and supercurrent distribution were distinctively different between the edge and the bulk. Our Heisenberg modeling showed that magnetic dopants stabilize anti-ferromagnetic spin correlation along the edge, which may contribute towards its robust superconductivity. Our observations hold implication for FST as potential platforms for topological quantum computation and superconducting spintronics.

据报道，铁硫族化物高温超导体 Fe(Se,Te) (FST) 表现出复杂的磁序和非平凡的能带拓扑结构，这可能会导致新的超导现象。然而，迄今为止，最近的研究主要集中在它的能带和自旋结构上，而其对未来设备应用至关重要的介观电子和磁响应尚未通过实验进行探索。在这里，我们使用扫描超导量子干涉装置显微镜，因为它对局部反磁化率和电流分布都敏感，以便对 FST 中的超流体密度和超电流进行成像。我们发现在具有 10% 间隙 Fe 的 FST 中，其磁结构被严重破坏，体积超导性被显着抑制，而边缘仍然保持强超导抗磁性。尽管磁穿透深度很长，但边缘主要承载超电流。超流体密度和超电流分布的温度依赖性在边缘和体积之间明显不同。我们的海森堡模型表明，磁性掺杂剂稳定了边缘的反铁磁自旋相关性，这可能有助于其稳健的超导性。我们的观察表明 FST 可以作为拓扑量子计算和超导自旋电子学的潜在平台。超流体密度和超电流分布的温度依赖性在边缘和体积之间明显不同。我们的海森堡模型表明，磁性掺杂剂稳定了边缘的反铁磁自旋相关性，这可能有助于其稳健的超导性。我们的观察表明 FST 可以作为拓扑量子计算和超导自旋电子学的潜在平台。超流体密度和超电流分布的温度依赖性在边缘和体积之间明显不同。我们的海森堡模型表明，磁性掺杂剂稳定了边缘的反铁磁自旋相关性，这可能有助于其稳健的超导性。我们的观察表明 FST 可以作为拓扑量子计算和超导自旋电子学的潜在平台。