Work

If an electrical current flows lengthwise through a metal band and a magnetic field is placed against the surface of the band at a right angle, a charge arises diagonally in the band. Known as the Hall effect, it comes about because the movement of the electrons is deflected by the magnetic field. In 1980, Klaus von Klitzing discovered the quantum Hall effect in an interface between a metal and a semiconductor in a very clean material. In this effect, changes in the magnetic field result in changes in what is known as Hall conductance that vary in steps of whole-number multiples of a constant.