氧化物稀释磁性半导体中极性依赖的高温铁磁性的电子结构起源

Electronic structure origins of polarity-dependent high-TC ferromagnetism in oxide-diluted magnetic semiconductors.

作者信息

Kittilstved Kevin R, Liu William K, Gamelin Daniel R

机构信息

Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA.

出版信息

Nat Mater. 2006 Apr;5(4):291-7. doi: 10.1038/nmat1616. Epub 2006 Mar 26.

DOI:10.1038/nmat1616

PMID:16565711

Abstract

Future spintronics technologies based on diluted magnetic semiconductors (DMSs) will rely heavily on a sound understanding of the microscopic origins of ferromagnetism in such materials. Discoveries of room-temperature ferromagnetism in wide-bandgap DMSs hold great promise, but this ferromagnetism remains poorly understood. Here we demonstrate a close link between the electronic structures and polarity-dependent high-TC ferromagnetism of TM(2+):ZnO DMSs, where TM(2+) denotes 3d transition metal ions. Trends in ferromagnetism across the 3d series of TM(2+):ZnO DMSs predicted from the energies of donor- and acceptor-type excited states reproduce experimental trends well. These results provide a unified basis for understanding both n- and p-type ferromagnetic oxide DMSs.

摘要

基于稀磁半导体（DMSs）的未来自旋电子学技术将严重依赖于对这类材料中铁磁性微观起源的深入理解。宽带隙DMSs中室温铁磁性的发现前景广阔，但这种铁磁性仍知之甚少。在此，我们证明了TM(2+):ZnO DMSs的电子结构与极性相关的高温铁磁性之间存在紧密联系，其中TM(2+)表示3d过渡金属离子。根据施主型和受主型激发态能量预测的TM(2+):ZnO DMSs的3d系列中铁磁性趋势与实验趋势吻合良好。这些结果为理解n型和p型铁磁氧化物DMSs提供了统一的基础。