Resonant spin tunneling in randomly oriented nanospheres of Mn-12 acetate

Article

关键词: SINGLE-MOLECULE MAGNET;    QUANTUM;    MAGNETIZATION;    MN-12-ACETATE;    DIFFRACTION;    CLUSTERS;    BEHAVIOR;    SYSTEMS;   

DOI  :  10.1103/PhysRevB.91.024404

来源: SCIE

【 摘 要 】

We report measurements and theoretical analysis of resonant spin tunneling in randomly oriented nanospheres of a molecular magnet. Amorphous nanospheres of Mn-12 acetate have been fabricated and characterized by chemical, infrared, TEM, x-ray, and magnetic methods. Magnetic measurements have revealed sharp tunneling peaks in the field derivative of the magnetization that occur at the typical resonant field values for the Mn-12 acetate crystal in the field parallel to the easy axis. Theoretical analysis is provided that explains these observations. We argue that resonant spin tunneling in a molecular magnet can be established in a powder sample, without the need for a single crystal and without aligning the easy magnetization axes of the molecules. This is confirmed by reanalyzing the old data on a powdered sample of nonoriented micron-size crystals of Mn-12 acetate. Our findings can greatly simplify the selection of candidates for quantum spin tunneling among newly synthesized molecular magnets.

【 授权许可】

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