Spin chirality in antiferromagnets offers new opportunities for spintronics. The kagome antiferromagnet ${\mathrm{Mn}}_3\mathrm{Sn}$ is a paradigmatic material in which the antiferromagnetic order parameter can be detected and controlled by electrical means. However, direct investigation of the magnetic texture of ${\mathrm{Mn}}_3\mathrm{Sn}$ has been challenging because of the tiny moment hosted in its magnetic octupole, hindering further clarification of this unique material. Here, we address this issue by observing the stray magnetic field from ${\mathrm{Mn}}_3\mathrm{Sn}$ using a diamond-based quantum scanning microscope. The spatially resolved intrinsic domains and domain walls in a high-quality single-crystalline ${\mathrm{Mn}}_3\mathrm{Sn}$ film quantitatively reveal the polarization angle of the magnetic octupole in the kagome plane, the domain's local magnetization, the domain wall's width and chirality, and the octupole order in domain walls. Our nanoscale investigation of ${\mathrm{Mn}}_3\mathrm{Sn}$, a powerful complement to macroscopic measurements, paves the road for developing chiral antiferromagnetism and its potential for spintronic applications.

Close

PrevNext

View figure in article

• Antiferromagnetism
• Domain walls
• Magnetic domains
• Optically detected magnetic resonance
• Scanning techniques