摘要
As is always accompanying temperature in physics fundamental principles, Boltzmann constant kB can be used to verify the accuracy of a thermometer. This paper presents a photoluminescent method to measure kB via temperature dependent fluorescence of phosphors. Diagram of a phosphor＇s energy levels was simplified to illustrate the principle of measurement. The relationship between kB and h＊c （Planck constant h multiplying light speed in vacuum c） was experimentally derived. Finally, the determined kB was 1.38065 x l0 23j/K. The determination could give a value of （1.38＋0.1） × 10 23 J/K even when the in-use spectrometer was with a poor resolution as about 2 nm. At the end, optimization of measuring conditions for the determination process was suggested.
As is always accompanying temperature in physics fundamental principles, Boltzmann constant kB can be used to verify the accuracy of a thermometer. This paper presents a photoluminescent method to measure kB via temperature dependent fluorescence of phosphors. Diagram of a phosphor＇s energy levels was simplified to illustrate the principle of measurement. The relationship between kB and h＊c （Planck constant h multiplying light speed in vacuum c） was experimentally derived. Finally, the determined kB was 1.38065 x l0 23j/K. The determination could give a value of （1.38＋0.1） × 10 23 J/K even when the in-use spectrometer was with a poor resolution as about 2 nm. At the end, optimization of measuring conditions for the determination process was suggested.
基金
Acknowledgements This work was jointly supported by the National Natural Science Foundation of China （Grant No. 61167007） and the Foundation of Aeronautics （No. 2012ZD56007）.
