Structure and magnetism in metastable bcc Co1-xMnx epitaxial films

被引：8

作者：

Kunimatsu, Kazuma ^{[1
,2
]}

Roy, Tufan ^{[3
]}

Okabayashi, Jun ^{[4
]}

Tsuchiya, Tomoki ^{[5
,6
]}

Ichinose, Tomohiro ^{[2
]}

Tsujikawa, Masahito ^{[3
,6
]}

Shirai, Masafumi ^{[3
,5
,6
]}

Mizukami, Shigemi ^{[2
,5
,6
]}

机构：

[1] Tohoku Univ, Grad Sch Engn, Dept Appl Phys, Sendai, Miyagi 9808579, Japan

[2] Tohoku Univ, Adv Inst Mat Res WPI AIMR, Katahira 2-1-1, Sendai, Miyagi 9808577, Japan

[3] Tohoku Univ, Res Inst Elect Commun, Sendai, Miyagi 9808577, Japan

[4] Univ Tokyo, Res Ctr Spectrochem, Tokyo 1130033, Japan

[5] Tohoku Univ, CSIS, CRC, Sendai, Miyagi 9808577, Japan

[6] Tohoku Univ, CSRN, Sendai, Miyagi 9808577, Japan

来源：

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS | 2022年 / 548卷

关键词：

Thin films; Disordered alloys; Metastable; X-ray magnetic circular dichroism; Ab-initio calculations; GROWTH;

D O I：

10.1016/j.jmmm.2021.168841

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Co-rich Co1-xMnx alloys have hcp or fcc disordered phase and those ferromagnetic orderings are significantly deteriorated with increasing Mn concentration x in bulk. On the other hand, those metastable bcc phases show properties attractive to magnetics and spintronics, as studied recently. Here, we report systematic study of structure and magnetism for epitaxial thin films. The single phase bcc Co1-xMnx (001) films were pseudomorphically grown on Cr(001) for 0.14 < x < 0.50 with a sputtering technique. The saturation magnetization was larger than that of pure Co for the films with x = 0.14 and 0.25 and smaller for the x = 0.34 films, disappearing completely for the x = 0.5 films. X-ray magnetic circular dichroism unveiled that this behavior stemmed from the composition dependence of elemental magnetic moments. Slight enhancement of magnetic moment of Co was observed in bcc alloy films. We also found that magnetic moments of Mn exceeded 2 mu(B) at the maximum and were not as high as theoretical values, approximately 3 mu(B), obtained from ab-initio calculation with coherent potential approximation. This difference is qualitatively understood in terms of microscopic Mn atom pairing with antiferromagnetic coupling, being suggested from the ab-initio band structure calculations based on special quasi-random structure of bcc Co1-xMnx.

引用

页数：8