Planar Hall effect in Hall sensors made from InP/InGaAs heterostructure

Room temperature planar Hall effect is investgated in a Hall sensor prepared from InP/InGaAs heterostructure containing triangel quantum well with two dimensional electron gas (2DEG) and is compared with that in a bulk GaAs Hall sensor. The heterostructure sensor investigated exhibits nearly three order of magnitude smaller planar Hall coefficient than the value corresponding to the transversal physical magnetoresistance coefficient. This is associated with a low planar magnetoresistance effect due to an extremely low thicknes of the electrically active layer. The ratio of the planar- to the transversal Hall voltage in the heterostructure Hall sensor is found to be lower by a factor of 50 than that in the bulk one. Thus, Hall sensors made from heterostructures with 2DEG are particularly suitable as elements of systems for precise measurements of arbitrarily oriented magnetic field.