A single monolayer of iron selenide grown on strontium titanate shows an impressive enhancement of superconductivity compared with the bulk¹, as well as a novel Fermi surface topology^2,3,4,5, extreme two-dimensionality, and the possibility of phonon-enhanced electron pairing^1,5. For films thicker than one unit cell, however, the electronic structure is markedly different, with a drastically suppressed superconductivity and strong nematicity appearing. The physics driving this extraordinary dichotomy of superconducting behaviour is far from clear. Here, we use low-temperature scanning tunnelling microscopy to study multilayers of iron selenide grown by molecular beam epitaxy, and find a stripe-type charge ordering instability that develops beneath the nematic state. The charge ordering is visible and pinned in the vicinity of impurities. And as it emerges in the strong limit of nematicity, it suggests that a magnetic fluctuation with a rather small wavevector may be competing with the ordinary collinear antiferromagnetic ordering in multilayer films. The existence of stripes in iron-based superconductors, which resemble the stripe order in cuprates, not only suggests that electronic anisotropy and correlation are playing an important role, but also provides a platform for probing the complex interactions between nematicity, charge ordering, magnetism and superconductivity in high-temperature superconductors.

与本体¹相比，在钛酸锶上生长的单层硒化铁显示出超导性的显着增强，并且具有新颖的费米表面拓扑结构^2,3,4,5，具有极高的二维性，并且声子增强的可能性电子配对^1,5。但是，对于比一个单位电池厚的膜，其电子结构显着不同，出现了大大抑制的超导性和强向列性。导致这种超导行为非同寻常的二分法的物理机制还远未弄清。在这里，我们使用低温扫描隧道显微镜研究分子束外延生长的多层硒化铁，并发现在向列态下形成的条纹型电荷有序不稳定性。电荷排序可见并固定在杂质附近。并且，当它出现在向列性的严格极限中时，它表明具有相当小的波矢的磁波动可能会与多层膜中的普通共线反铁磁有序竞争。铁基超导体中存在条纹，