Magnetic skyrmions have raised high hopes for future spintronic devices. For many applications, it would be of great advantage to have more than one metastable particle-like texture available. The coexistence of skyrmions and antiskyrmions has been proposed in inversion-symmetric magnets with exchange frustration. However, so far only model systems have been studied and the lifetime of coexisting metastable topological spin structures has not been obtained. Here, we predict that skyrmions and antiskyrmions with diameters below 10 nm can coexist at zero magnetic field in a Rh/Co bilayer on the Ir(111) surface—an experimentally feasible system. We show that the lifetimes of metastable skyrmions and antiskyrmions in the ferromagnetic ground state are above one hour for temperatures up to 75 and 48 K, respectively. The entropic contribution to the nucleation and annihilation rates differs for skyrmions and antiskyrmions. This opens the route to the thermally activated creation of coexisting skyrmions and antiskyrmions in frustrated magnets with Dzyaloshinskii–Moriya interaction.

磁性斯格明子给未来的自旋电子器件带来了厚望。对于许多应用来说，拥有不止一种可用的亚稳态粒子状纹理将具有很大的优势。斯格明子和反斯格明子的共存已被提出在具有交换挫败的反演对称磁体中。然而，迄今为止仅研究了模型系统，并没有获得共存亚稳态拓扑自旋结构的寿命。在这里，我们预测直径低于 10 nm 的斯格明子和反斯格明子可以在零磁场下共存于 Ir(111) 表面的 Rh/Co 双层中——这是一个实验上可行的系统。我们表明，在高达 75 K 和 48 K 的温度下，亚稳态斯格明子和反斯格明子在铁磁基态下的寿命分别超过一小时。斯格明子和反斯格明子的熵对成核和湮灭速率的贡献不同。这开辟了通过 Dzyaloshinskii-Moriya 相互作用在受挫磁体中热激活共存斯格明子和反斯格明子的途径。