School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
Beijing Laboratory for Electron Microscopy, Institute of Physics, CAS, Beijing 100190, China.
Nat Commun. 2016 Dec 8;7:13497. doi: 10.1038/ncomms13497.
Emerging for future spintronic/electronic applications, magnetic semiconductors have stimulated intense interest due to their promises for new functionalities and device concepts. So far, the so-called diluted magnetic semiconductors attract many attentions, yet it remains challenging to increase their Curie temperatures above room temperature, particularly those based on III-V semiconductors. In contrast to the concept of doping magnetic elements into conventional semiconductors to make diluted magnetic semiconductors, here we propose to oxidize originally ferromagnetic metals/alloys to form new species of magnetic semiconductors. We introduce oxygen into a ferromagnetic metallic glass to form a CoFeTaBO magnetic semiconductor with a Curie temperature above 600 K. The demonstration of p-n heterojunctions and electric field control of the room-temperature ferromagnetism in this material reflects its p-type semiconducting character, with a mobility of 0.1 cm V s. Our findings may pave a new way to realize high Curie temperature magnetic semiconductors with unusual multifunctionalities.
新兴的自旋电子/电子应用，由于其具有新功能和器件概念的潜力，磁性半导体引起了人们的极大兴趣。到目前为止，所谓的稀磁半导体吸引了很多关注，但要将其居里温度提高到室温以上，特别是基于 III-V 半导体的居里温度提高到室温以上，仍然具有挑战性。与将磁性元素掺杂到传统半导体中以形成稀磁半导体的概念相反，我们在这里提出通过氧化原本的铁磁金属/合金来形成新的磁性半导体。我们将氧引入铁磁金属玻璃中，形成居里温度高于 600K 的 CoFeTaBO 磁性半导体。在该材料中 p-n 异质结的演示和室温铁磁性的电场控制反映了其 p 型半导体特性，迁移率为 0.1cmV s。我们的发现可能为实现具有异常多功能性的高居里温度磁性半导体开辟一条新途径。
