Hall nano-probes fabricated by focused ion beam

Hall magnetometers with active areas down to 100 x 100 nm(2) were fabricated patterning gold and Si-doped GaAs films by focused ion beam. For GaAs probes, electrical characterization shows that the magnetic flux sensitivity is better than 10(-2)Phi(0) at room temperature. Hall nano-probes made of gold can work down to liquid helium temperature with magnetic flux sensitivity 10(-1)Phi(0).