Low magnetic field mapping using an InGaAs-AlGaAs-GaAs 2 DEG Hall sensor

A new method of low magnetic field mapping using a two dimensional electron gas (2DEG) AlGaAs-InGaAs-GaAs Hall device, which was designed and optimised with respect to the measurements of low magnetic fields, using an x-y stepper motor scanner driven by a PC is reported. The scanner was used to map features in bank note detection, and magnetic digital signals of 50 /spl mu/T magnitude were measured.