CaMn2Al10: Itinerant Mn magnetism on the verge of magnetic order

Article

关键词: SPIN FLUCTUATIONS;    CRYSTAL-GROWTH;    QUANTUM;    SUPERCONDUCTIVITY;    FERROMAGNETISM;    METAL;    COEXISTENCE;    BEHAVIOR;    IRON;    YB;   

DOI  :  10.1103/PhysRevB.92.020413

来源: SCIE

【 摘 要 】

We report the discovery of CaMn2Al10, a metal with strong magnetic anisotropy and moderate electronic correlations. Magnetization measurements find a Curie-Weiss moment of 0.83 mu(B)/Mn, significantly reduced from the Hund's rule value, and the magnetic entropy obtained from specific heat measurements is correspondingly small, only approximate to 9% of R ln 2. 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 chi is anisotropic below 20 K, with a maximum ratio of chi([010])/chi([001]) approximate to 3.5. A strong power-law divergence chi(T) similar to T-1.2 below 20 K implies incipient ferromagnetic order with a low Curie temperature T-C < 2 K. Our experiments indicate that CaMn2Al10 is a rare example of a system where the weak and itinerant Mn-based magnetism is poised on the verge of order.

【 授权许可】

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