宏觀量子現象之實現與整合於科學計量學上之應用

Abstract

2019 年國際單位制之重新定義為科學測量史上之重要里程碑。此次重新定義旨在建立依更為精確及普遍的基礎物理量單位，以確保其永久穩定性與可用性。其中最為重要之改變為質量基本單位的重新定義，此重新定義消除了過往國際單位對於人造標準器之依賴。 於 2019 年以前，質量基本單位的定義是通過一名為國際千克標準器之人造元件來達成標準統一。此國際千克標準元件為一圓柱型鉑銥合金，長期存放於法國國家標準局內。然而，考量其固有限制，諸如不可預期之汙染以及時變性耗損，重新定義質量單位之可能性探索一直為科學計量學中最為重要的議題。經過科學家及計量學家多年來的研究與探索，質量標準之定義由人造標準器的規範轉換為一精確定義之普朗克常數 (h)。 普朗克常數為一物理學中之基本自然常數，其描述一光子之能量與頻率之相依性。經由精確設計之實驗可建立質量與普朗克常數之聯繫，並藉此以達成一更具穩定性與普世性之質量基本單位之計量。 質量單位的重新定義帶來幾個重要的好處，涵蓋了標準計量實驗之穩定性與可重複性、標準質量單位之普世性以及質量標準因果鍊之可傳播性。此外，此重新定義進一步拓展了多領域之科學進展的可能性，特別在需要精確及可追溯的質量量測領域，諸如製造業、製藥業以及基礎科學研究。 為了實現此重新定義， 科學家與計量學家開發了一系列專業的實驗技術，如 X-射線晶體密度計量法(XRCD method)及基布爾天秤(Kibble balance)。基布爾天秤為一複雜之電機儀器，其通過平衡一待測物之重量與電磁力來達成建構質量與普朗克常數之關聯，並藉此計量待測物之質量。此實驗技法通過電磁技術及機械測量之整合建立了質量與普朗克常數兩者之直接關聯。目前以基布爾天秤為核心進行的質量計量實驗仍無法實現新質量標準之穩定性及普世性，肇因於人造標準電阻器之使用。在此論文中，我們提出了一種解決人造電阻標準器所造成的新質量標準實現之阻礙。我們證明通過集成多種宏觀量子現象，可實現一無人造電阻標準器之基布爾天秤質量計量技法。此技法通過量子力學實現巨觀的質量計量， 解決了人造標準電阻器對於質量標準實驗之限制。此實驗結果展示了一種通過集成宏觀量子現象以實現基於國際單位新制之計量實驗之方法論。

The year 2019 marked a significant milestone in the history of scientific measurement with the redefinition of the International System of Units (SI). The redefinition aimed to establish a more precise and universal basis for fundamental units, ensuring their long-term stability and accessibility. One of the most notable changes was the redefinition of the kilogram since it eliminates the use of a physical artifact standard in the SI definition. Prior to 2019, the kilogram was defined by a physical artifact known as the International Prototype of the Kilogram (IPK), a platinum-iridium cylinder housed at the International Bureau of Weights and Measures (BIPM) in France. However, concerns about the IPK's inherent limitations, such as susceptibility to contamination and physical deterioration, necessitated a new approach to redefine the kilogram. The redefinition of the kilogram was realized through a shift from a physical prototype to a fundamental constant of nature, the Planck constant (h). The Planck constant, a fundamental constant of quantum physics, relates the energy of a photon to its frequency. By linking the kilogram to the Planck constant, the redefinition provided a more stable and accessible basis for the unit, independent of any physical object. The redefinition of the kilogram brought several significant benefits. Firstly, it enhanced the stability and reproducibility of the unit, ensuring consistent measurements across different locations and times. Secondly, it facilitated the dissemination of the unit by enabling the realization of the kilogram in various laboratory settings worldwide. Moreover, this redefinition opened up possibilities for further scientific advancements, particularly in areas requiring precise and traceable mass measurements, such as manufacturing, pharmaceuticals, and fundamental research. To achieve this redefinition, advanced experimental techniques, such as the Kibble balance, were employed. The Kibble balance, a sophisticated electromechanical instrument, balances the weight of an object against an electromagnetic force, which is directly related to the Planck constant. This approach enables the determination of mass based on electrical and mechanical measurements, thereby establishing a direct connection between mass and the fundamental constant. The current challenge for the Kibble balance experiment is the usage of a non-stable artifact resistance standard which limits its precision and the standard dissemination. In this thesis, a novel approach to resolving this issue is presented. The thesis demonstrates that by integrating multiple macroscopic quantum phenomena, an artifact-standard-free Kibble balance experiment can be achieved, allowing for the realization of macroscopic mass from quantum mechanics. This achievement showcases a methodology for realizing new SI units through a quantum-system integrating approach.