使用标准参考材料3451验证电磁和热磁传输测量
Matt Beekman1, Matteo Benedetti1, Deja Dominguez1
1Department of Physics, California Polytechnic State University, San Luis Obispo, California 93407, USA.
The Review of scientific instruments
|November 20, 2024
概括
一种新的方法验证了使用单一NIST标准的电阻,Seebeck,Hall和Nernst系数. 这简化了材料中电荷传输特性测量的验证.
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
- 固态物理 固态物理
背景情况:
- "四系数方法"使用电阻 (ρ),西贝克系数 (S),霍尔系数 (RH) 和内斯特系数 (Q) 来研究材料电子结构.
- 现有的参考材料可用于验证 ρ 和 S 的测量,但不能用于 RH 和 Q.
研究的目的:
- 用单一的参考材料证明所有四个运输系数 (ρ,S,RH和Q) 的验证.
- 为NIST SRM 3451提供RH和Q数据,以补充现有的 ρ和S数据.
主要方法:
- 使用国家标准与技术研究所 (NIST) 的Seebeck系数标准参考材料® (SRM) 3451 (Bi2Te3+x).
- 在80400K的温度范围内测量SRM 3451的 ρ,S,RH 和 Q.
- 验证了对磁和热磁传输性能的测量系统.
主要成果:
- 通过使用NIST SRM 3451.1,成功验证了 ρ,S,RH 和 Q 的测量.
- 报告了SRM 3451的新RH和Q数据,在80400K之间.
- 消除了对验证进行实验室间样本交换的需要.
结论:
- NIST SRM 3451作为一个单一的参考材料,用于验证所有四个关键电荷传输系数的测量.
- 这些发现有助于精确验证磁和热磁测量系统.
- 这项工作为凝聚物质物理学和材料科学中的材料表征建立了关键标准.
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