Unconventional magnetism in kagome magnet Co₃Sn₂S₂investigated by local probes

Shandite Co₃Sn₂S₂ has been considered a ferromagnet with c-axis as its easy axis. However, recently, there have been reports suggesting the presence of spin glass or antiferromagnetism, challenging our understanding of the ground state. In order to unravel the magnetism of Co₃Sn₂S₂, we have conducted magnetic imaging studies using XMCD-PEEM and MOKE. The magnetic domain pattern is unusual, spontaneously forming magnetic bubbles. However, no antiferromagnetic phases are detected. The magnetic domain pattern displays thermal hysteresis consistent with the thermal hysteresis in temperature dependent magnetization. We can explain most features of the magnetization based on the magnetic domain evolution.