The International System of Units (SI) is the world's most widely used system of measurement, used every day in commerce and science, and is the modern form of the metric system. It currently comprises the meter (m), the kilogram (kg), the second (s), the ampere (A), the kelvin (K), the candela (cd) and the mole (mol)). The system is changing though, units and unit definitions are modified through international agreements as the technology of measurement progresses, and as the precision of measurements improves. The SI is now being redefined based on constants of nature and their realization by quantum standards. Therefore, the underlying physics and technologies will receive increasing interest, and not only in the metrology community but in all fields of science. This book introduces and explains the applications of modern physics concepts to metrology, the science and the applications of measurements. A special focus is made on the use of quantum standards for the realization of the forthcoming new SI (the international system of units). The basic physical phenomena are introduced on a level which provides comprehensive information for the experienced reader but also provides a guide for a more intense study of these phenomena for students.The International System of Units (SI) is the world's most widely used system of measurement, used every day in commerce and science, and is the modern form of the metric system. It currently comprises the meter (m), the kilogram (kg), the second (s), the ampere (A), the kelvin (K), the candela (cd) and the mole (mol)). The system is changing though, units and unit definitions are modified through international agreements as the technology of measurement progresses, and as the precision of measurements improves. The SI is now being redefined based on constants of nature and their realization by quantum standards. Therefore, the underlying physics and technologies will receive increasing interest, and not only in the metrology community but in all fields of science. This book introduces and explains the applications of modern physics concepts to metrology, the science and the applications of measurements. A special focus is made on the use of quantum standards for the realization of the forthcoming new SI (the international system of units). The basic physical phenomena are introduced on a level which provides comprehensive information for the experienced reader but also provides a guide for a more intense study of these phenomena for students.

Sep 21, 20154 citations

Quantum Metrology and Quantum Sensors

WORLD SCIENTIFIC eBooksJul 9, 20240 citations

Advancing quantum metrology in China's power grids

Shisong Li

In November 2018, during the 26th General Conference on Weights and Measures (CGPM) in Versailles, France, a landmark resolution was adopted to redefine four base units of the International System of Units (SI)(https://www.bipm.org/en/committees/cg/cgpm/26-2018/resolution-1). The kilogram, mole, ampere, and kelvin were redefined in terms of fundamental physical constants: the Planck constant $(h)$ , the Avogadro constant $(N_{\mathrm{A}})$ , the elementary charge $(e)$ , and the Boltzmann constant $(k)$ , respectively. As illustrated in Figure 1(a), the new SI framework defines all seven base units based on fundamental constants, marking a complete transition of metrology into the quantum era. This system has been in effect globally since May 20, 2019, on World Metrology Day.In November 2018, during the 26th General Conference on Weights and Measures (CGPM) in Versailles, France, a landmark resolution was adopted to redefine four base units of the International System of Units (SI)(https://www.bipm.org/en/committees/cg/cgpm/26-2018/resolution-1). The kilogram, mole, ampere, and kelvin were redefined in terms of fundamental physical constants: the Planck constant$(h)$, the Avogadro constant$(N_{\mathrm{A}})$, the elementary charge$(e)$, and the Boltzmann constant$(k)$, respectively. As illustrated in Figure 1(a), the new SI framework defines all seven base units based on fundamental constants, marking a complete transition of metrology into the quantum era. This system has been in effect globally since May 20, 2019, on World Metrology Day.

iEnergySep 1, 20241 citation

(h)

, the Avogadro constant

(N_{\mathrm{A}})

, the elementary charge

(e)

, and the Boltzmann constant

(k)

, respectively. As illustrated in Figure 1(a), the new SI framework defines all seven base units based on fundamental constants, marking a complete transition of metrology into the quantum era. This system has been in effect globally since May 20, 2019, on World Metrology Day.