The Elementary Charge for the Definition and Realization of the Ampere

Abstract

The elementary charge e is one of the seven defining constants in the revised International System of Units (SI). Here, the determination of the elementary charge with the highest precision is discussed, including the results of the special CODATA adjustment leading to the fixed value of e. The various options to realize the ampere and the other electrical units in the revised SI, either through the counting of electrons by using single-electron tunneling devices or through the Josephson and quantum Hall effect, respectively, are further elucidated.

An Alternative Approach to Simulate the Power Conversion Efficiency of Bulk Heterojunction Organic Solar Cells

“…L ITO [cm] 0.5 [58] 1 [43] 0.2 [45] R sheetITO ½Ω sq À1 ] 13.7 [41] n 3.2 Â 10 22 [59] N t:bulk 2.1 Â 10 19 [39] N t:surf 6.3 Â 10 18 [39] T [K] 300 [18] P in [Wm À2 ] 1000 [24] e [C] 1.6 Â 10 À19 [60] h [m 2 kgs À1 ] 6.63 Â 10 À34 [61] ε 0 [Fm À1 ] 8.85 Â 10 À12 [62] k [m 2 kgs À2 K À1 ] 1.38 Â 10 À23 [63] significantly than in OSC2 ( Figure 2b) and OSC3 (Figure 2c) over the whole thickness range and cross each other. The cause of this discrepancy is not very obvious except that OSC1 contains a fullerene acceptor and it also has a layer of SiO 2 before the ITO in its structure of: glass (1 mm)/SiO 2 (10 nm)/ITO (150 nm)/PEDOT:PSS (50 nm)/P3HT:PCBM/LiF (1 nm)/Al (100 nm).…”

Operating Temperature of Nonfullerene Acceptor‐Based Bulk Heterojunction Organic Solar Cells

“…T [K] 300 [29] e [C] 1.6 Â 10 À19 [61] h [m 2 kgs À1 ] 6.63 Â 10 À34 [62] ε 0 [Fm À1 ] 8.85 Â 10 À12 [63] k [m 2 kgs À2 K À1 ] 1.38 Â 10 À23 [64] ε c 0.9 [26] σ sb [Wm À2 K À4 ] 5.67 Â 10 À8 [26] N c, N v [m À3 ] 1.65 Â 10 26 [65] N tc, N tv [cm À3 ] 7.3 Â 10 15 [66] β 0 n , β þ n [cm 3 s À1 ] 2.5 Â 10 À10 [26,31] β 0 p , β À p [cm 3 s À1 ] 5 Â 10 À10 [26,31] T co , T vo [K] 500 [26,31] v [ms À1 ] 0.5…”

New Eras in Physics

“…[1] With this, the French metrology institution BIPM will give up its traditional role as host of the famous "Grand K", the kilogram prototype, which is to be replaced by a fixed value of the Planck constant h. [2] At the same time, also the elementary charge e, [3] the Boltzmann constant k, [4] and the Avogadro constant N A [5] received new definitions so that in the future all seven SI units will be defined in terms of physical constants. [1] With this, the French metrology institution BIPM will give up its traditional role as host of the famous "Grand K", the kilogram prototype, which is to be replaced by a fixed value of the Planck constant h. [2] At the same time, also the elementary charge e, [3] the Boltzmann constant k, [4] and the Avogadro constant N A [5] received new definitions so that in the future all seven SI units will be defined in terms of physical constants.…”

“…On 16 November 2018, the 26th meeting of the General Conference on Weights and Measures in Versailles adopted a resolution on the revision of the International System of Units (SI). [1] With this, the French metrology institution BIPM will give up its traditional role as host of the famous "Grand K", the kilogram prototype, which is to be replaced by a fixed value of the Planck constant h. [2] At the same time, also the elementary charge e, [3] the Boltzmann constant k, [4] and the Avogadro constant N A [5] received new definitions so that in the future all seven SI units will be defined in terms of physical constants. These changes will come into effect on 20 May 2019, and on this occasion Annalen der Physik will publish a special issue "The Revised SI: Fundamental Constants, Basic Physics and Units", edited by our Editorial Advisory Board member Klaus Blaum (Max Planck Institute for Nuclear Physics Heidelberg), Dmitry Budker (Johannes Gutenberg University of Mainz), Andrey Surzhykov (Technical University and Physikalisch-Technische Bundesanstalt -PTB, Braunschweig), and Joachim H. Ullrich (President of the PTB, the National Metrology Institute of Germany) (Figure 1).…”