Magnetic domains in a uniaxial magnet Dy3Al2

The rare-earth intermetallic Dy3Al2 is a low-temperature permanent magnet with temperature-induced spin reorientation transition. In this work, we report the observation of magnetic domains in lamellae of Dy3Al2 using Liquid-Nitrogen cryo-Lorentz transmission electronic microscopy (cryo-LTEM) above TSR (70 K). We studied the magnetic field dependence of domain evolution from stripe domains at zero magnetic field to the saturation state. When the easy axis lies within the lamella plane, stripe domains gradually narrow and disappear as the applied field increases. The saturation field decreases with the increasing temperature. In the presence of misalignment between the easy axis and external field, stripe domains evolve into type-II magnetic bubbles (as small as 50–60 nm). The spin configuration was further verified by utilizing differential phase contrast scanning transmission microscopy and micromagnetic simulations.