The origin of switching noise in GaAs/AlGaAs lateral gated devices

摘要

We have studied at low temperatures the switching (telegraph) noise in quantum point contacts fabricated on GaAs/AlGaAs heterostructures and introduce a model for its origin which explains why the noise can be suppressed by cooling the samples with a positive bias applied to the gates. This model depends on there being a small tunnel current of electrons from gate to channel and we have detected such a current at the level of View the MathML source10-20A using a quantum corral fabricated on similar material.