Abstract
We report the discovery of , a metal with strong magnetic anisotropy and moderate electronic correlations. Magnetization measurements find a Curie-Weiss moment of , significantly reduced from the Hund's rule value, and the magnetic entropy obtained from specific heat measurements is correspondingly small, only of . These results imply that the Mn magnetism is highly itinerant, a conclusion supported by density functional theory calculations that find strong Mn-Al hybridization. Consistent with the layered nature of the crystal structure, the magnetic susceptibility is anisotropic below 20 K, with a maximum ratio of . A strong power-law divergence below 20 K implies incipient ferromagnetic order with a low Curie temperature . Our experiments indicate that is a rare example of a system where the weak and itinerant Mn-based magnetism is poised on the verge of order.
- Received 27 April 2015
DOI:https://doi.org/10.1103/PhysRevB.92.020413
©2015 American Physical Society