The features of magnetotransport properties of the Mn δ-doped GaAs structure with multiple conduction channels

The work examines the features of the magnetotransport and magnetooptical properties of a GaAs structure with a Mn δ-layer located near an In _0.25Ga _0.75As/GaAs quantum well with high charge carrier mobility. It is shown that in the initial structure, conduction occurs predominantly in the quantum well region, that leads to the dominance of magnetotransport phenomena of a Lorentzian nature (ordinary Hall effect and positive magnetoresistance). After suppression of the conduction channel through the quantum well using ion irradiation, an anomalous Hall effect and negative resistance are observed. It has been established that the experimental magnetic field dependences of the Hall resistance in ferromagnetic nanostructures with multiple conduction channels may not reflect the real magnetic properties of the structures.