在基于二维五角形的XN2 (X = B,Al和Ga) 结构中,高尼尔温度和磁性调制具有自旋极化非金属原子
1College of Physics, Sichuan University, Chengdu, 610065, China. hongzhang@scu.edu.cn.
Physical chemistry chemical physics : PCCP
|January 17, 2025
概括
基于五角形的二维XN2材料表现出有希望的反铁磁半导体性能. 外界场可以调整它们的磁顺序,并增强用于自旋电子应用的性能.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 量子化学 是一个量子化学.
背景情况:
- 传统的磁性半导体经常受到低磁时刻和临界温度的影响,限制了它们的实际应用.
- 磁性半导体中的自旋极化非金属原子通常因性能限制而被忽视.
研究的目的:
- 研究基于五角形的二维 (2D) XN2 (X = B,Al,Ga) 材料的磁性特性.
- 探索磁性的起源和通过外部刺激调整磁性质的潜力.
主要方法:
- 使用第一原理计算来确定电子和磁性.
- 对自旋密度分布和分子轨道的分析阐明了磁性的来源.
- 使用伊辛格模型进行蒙特卡洛模拟,以预测尼尔温度.
主要成果:
- XN2结构被确定为反铁磁半导体,带隙范围从2.15 eV到2.42 eV.
- 磁源归因于原子的抗键轨道 (π*2p和π*2p).
- 尼尔温度 (TN) 预计分别为B,Al和Ga的高达136K,266K和477K.
结论:
- 发现了一种基于XN2材料中的共价键的新型自旋极化现象.
- 外界场可以诱导从反铁磁到铁磁的阶段过渡,调整带间隙,增强磁矩.
- 这些发现表明,由于提高了性能特征,spintronic设备中的XN2材料具有显著的潜力.
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