Magnetic phase separation in single-crystal dysprosium at 97–187 K was investigated using aberration-corrected Lorentz microscopy. The high-resolution Lorentz microscopy combined with the transport-of-intensity equation method successfully visualized the in-plane magnetization distribution of the coexisting magnetic phases. The onset of a phase transition from the ferromagnetic (FM) phase to helical antiferromagnetic (HAFM) phase was observed at $\sim 100\mathrm{K}$, and the two nanoscale phases coexisted up to $\sim 140\mathrm{K}$. The volume fraction of the FM phase decreased with increasing temperature, eventually resulting in the formation of static magnetic solitons, which are isolated single domains of the FM phase, at around 130 K. We also performed the in situ observation of the HAFM phase at 142 K by applying an external magnetic field normal to the helical axis. With increasing field, a distorted HAFM phase emerged and the nanoscale phase separation between the HAFM phase and the fan phase subsequently occurred from $\sim 6$ to $\sim 11\mathrm{kOe}$. It was proven that the boundaries between these nanoscale coexisting phases were perpendicular to the $z$ axis, which is the rotation axis common to the modulated magnetic structures.

中文翻译：

---

像差校正的洛伦兹显微镜对observation中纳米级磁性相分离的真实空间观察

使用像差校正的洛伦兹显微镜研究了97-187 K时single中单晶的磁相分离。高分辨率洛伦兹显微镜与强度输运方程方法相结合，成功地可视化了共存磁相的面内磁化分布。观察到从铁磁（FM）相到螺旋反铁磁（HAFM）相的相变开始$〜100\mathrm{ķ}$，并且两个纳米级相共存直至 $〜140\mathrm{ķ}$。FM相的体积分数随温度的升高而降低，最终导致形成静磁孤子，它们是FM相的单个畴，大约在130 K左右。我们还在142°进行了HAFM相的原位观察通过施加垂直于螺旋轴的外部磁场来获得K。随着场的增加，出现了扭曲的HAFM相，随后HAFM相与扇形相之间发生了纳米级相分离。$〜6$ 到 $〜11O$。事实证明，这些纳米级共存相之间的边界垂直于纳米线。$ž$ 轴，这是调制磁结构共有的旋转轴。