四种测量玻尔兹曼常数的原级温度计研究综述

Review of research on four primary thermometers for measuring Boltzmann constant

第26届国际计量大会批准了利用基本常量重新定义国际单位制(SI)。其中,温度单位“开尔文(K)”采用玻尔兹曼常量(k)重新定义。精确测量玻尔兹曼常量是重新定义开尔文和复现热力学温度的关键,本文详细介绍了用于测量玻尔兹曼常量的四种原级温度计:声学气体温度计、介电常量气体温度计、约翰逊噪声温度计、多普勒展宽温度计。阐述了四种原级温度计的工作原理、主要参数、实际应用情况,分析并探讨了它们对玻尔兹曼常量值修订起到的贡献。最后对原级测温方法未来发展方向进行总结与展望,为热力学温度的复现和传递提供研究支撑。

The 26th General Conference on Weights and Measures(CGPM)approved the redefinition of the International System of Units(SI)using fundamental constants.The temperature unit“Kelvin(K)”will be redefined using Boltzmann constant(k).Accurate measurement of Boltzmann constant is the key to redefining Kelvin and reproducing thermodynamic temperature.In this paper,four kinds of primary thermometers used for measuring Boltzmann constant are introduced in detail,namely acoustic gas thermometery(AGT),dielectric-constant gas thermometery(DCGT),Johnson noise thermometery(JNT)and Doppler broadening thermometery(DBT).The working principle,main parameters and practical application of the four primary thermometers are expounded,and their contributions to the revision of Boltzmann constant value is explained.Finally,the future development direction of the primary temperature measurement method is summarized and prospected,which provides research support for the reproduction and transfer of thermodynamic temperature.