具有双负电磁参数的随机元材料在密集的CuCr2Se4-CoCr2Se4二元旋转中
Jun Cao1, Chengsheng Wang1, Zechao Xu1
1College of Chemical Engineering, State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, Jiangsu 210009, P.R. China. lyan@njtech.edu.cn.
Dalton transactions (Cambridge, England : 2003)
|September 18, 2025
概括
这项研究引入了可调节的双负元材料,使用铜和的化复合材料. 这些材料在先进的电磁应用中表现出负电容性和透性.
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
- 电磁主义 电磁主义
背景情况:
- 对先进的电磁应用而言,具有同时负导电性 (ε < 0) 和负透性 (μ < 0) 的元材料至关重要.
- 基于的旋复合材料显示出双负元材料 (DNM) 的潜力,但实现可调节性质是具有挑战性的.
研究的目的:
- 为了合成和表征 (1 - x) CuCr2Se4·xCoCr2Se4复合材料.
- 在MHz频率范围内实现和调整双负电磁性质.
- 了解这些复合材料中负电容性和透性背后的机制.
主要方法:
- 固态反应合成 (1 - x) CuCr2Se4·xCoCr2Se4样本.
- 在MHz频率范围内测量电磁性质.
- 使用德鲁德模型进行分析,并研究磁共振现象.
主要成果:
- 在特定的MHz频率范围内观察到双负性质,对于不同的CoCr2Se4度 (x=0.2,0.4,0.6).
- 负电容性归因于非局部载体的血振荡 (德鲁德模型).
- 负透性是由于低导电性而抑制的旋流造成的,增强了磁共振.
结论:
- 添加CoCr2Se4有效调节基于CuCr2Se4的复合材料的电磁性质.
- 复合材料设计减少了电磁衰减,提高了磁性响应.
- 这项研究促进了对低频应用的单相双负元材料的理解和开发.
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