Scientists find liquid crystal-like magnetic state in YbMnBi₂

Rice University researchers found that YbMnBi₂ retains directional spin fluctuations after conventional magnetic order disappears, a state they call a magnetic liquid crystal. The finding challenges the tilted-spin explanation for the material's large anomalous Hall effect and points to ytterbium-manganese interactions.

• Manganese spins in YbMnBi₂ keep directional fluctuations after magnetic order fades
• Neutron experiments at Oak Ridge showed the spins remain essentially collinear
• Directional fluctuations vanish in CaMnBi₂, which lacks magnetic ytterbium
• Ytterbium ions carry their own magnetic moments that interact with manganese spins