在 (t_{2g}) ^{4} 系统的线性反铁磁体中,对非同位素磁双极的铁顺序
Norimasa Sasabe1, Masaichiro Mizumaki1, Takayuki Uozumi2
1Japan Synchrotron Radiation Research Institute, SPring-8 Kouto, Sayo, Hyogo 679-5198, Japan.
Physical review letters
|December 10, 2023
概括
X射线磁圆二重力学可以检测二氧化卢 (RuO2) 中的磁时刻与对线反铁磁力学 (AFM). 这种技术有助于识别磁相,如范弗莱克磁体或激发性AFM.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
背景情况:
- 像RuO2这样的材料中的线性反铁磁 (AFM) 具有独特的对称性.
- 时间逆向对称性破坏对于理解这些系统中的磁现象至关重要.
- 在AFM状态中检测磁矩是具有挑战性的,但对于材料表征至关重要.
研究的目的:
- 探索使用X射线磁性圆形二元体 (XMCD) 探测RuO2的磁性特性与对线AFM的可行性.
- 为了研究晶体对称性如何影响AFM状态中的磁二极子运算器.
- 建立XMCD作为在 (t2g) 4系统中区分不同磁相的工具.
主要方法:
- 对X射线磁性圆形二元化的理论分析.
- 考虑晶体对称性和时间逆转对称性破坏.
- 探究异构磁二极运算子t及其与磁二极术语Tz.关系的研究.
主要成果:
- 已经证明,XMCD是一种可行的技术,可以用直线AFM检测RuO2中的磁矩.
- 沿[010]方向的剩余期望向量t被确定为诱导XMCD信号的源.
- 在XMCD中磁二极体术语Tz直接与异性磁二极体运算符有关.
结论:
- 即使在反铁磁材料中,XMCD也可以有效地检测磁矩.
- 这种技术提供了一种途径,以区分磁相,包括范弗莱克类型的假磁体和 (t2g) 4系统中的刺激性AFM.
- 该研究强调了XMCD在先进磁相测定方面的潜力.
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