Von Klitzing constant

Examples of the observational equations are given in Table 2. In that table, r H and vb are transition frequencies in hydrogen and deuterium such as those given in Table 3 below, Kj is the Josephson constant, which is characteristic of the Josephson effect, and Rk is the von Klitzing constant, which is characteristic of the quantum Hall effect. Note that Ex(riLj)/h is proportional to cRoo and independent of h, hence h is not an adjusted constant in these equations. 

Here p is either integer (p = 1,2,3, etc.) for the integer quantum Hall effect, first measured by von Klitzing25 at cryogenic temperatures [14], or a rational fraction (p 1 /3, 1/5, 5/2, etc.) for the fractional quantum Hall effect, first measured by Tsui, Stormer, and Laughlin [15]. The very well measured quantity ez/h = 25.81280745 kQ is called the von Klitzing constant, although it should also be called Landauer s constant. 

The Planck constant can be obtained by comparing a watt of mechanical energy measured in SI units to a watt of electrical energj measured in terms of the Josephson constant Kj = 2e/h) and von Klitzing constant (i K = h/e ) in the combination... 

The numerical value of F to be used in coulometric chemical measurements is 96485.3401(48) [5.0 x 10 ] when the relevant current is measured in terms of representations of the volt and ohm based on the Josephson and quantum Hall effects and the internationally adopted conventional values of the Josephson and von Klitzing constants Kj 9o and Fk-9o given in Table IV. 

Conventional value of von Klitzing constant Hk90 25,812.807 n Exact... 

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