Metrology
In electrical quantum metrology, semiconductor devices are used in two areas. For one, there is reproduction of electrical resistance values by the quantum-Hall effect with uncertainties below one part in a billion. Another is the high mobile electron devices used in the fabrication of single-electron pumps that allows controlled transport of electrons passing the device one by one. Much controversy has been put to this since it is possible that they might allow the redefinition of the electrical current as a product of frequency and electron charge such that the current unit Ampere can be connected to a spatial and time-invariant fundamental constant, which is the elementary charge.
working in a Metrology company
