Quantum corrections to the conductivity and anomalous Hall effect in InGaAs quantum wells with a spatially separated Mn impurity

Magnetotransport in heterostructures with spatial separation of the Mn magnetic impurity and an InGaAs quantum well is studied. An analysis of the observed effect of weak localization using the Hikami–Larkin–Nagaoki formula leads to an anomalously small value (0.4) of the prefactor. Obtained data indicate that inelastic $e$–$e$ scattering can be the dominant dephasing mechanism in the structures under study. Analysis of the conductivity and magnetoresistance indicates the dominant role of spin-dependent scattering at fluctuations in the magnetic subsystem, which is consistent with an increase in the amplitude of the negative magnetoresistance and an increase in the Drude conductivity as a result of cooling. The nature of the anomalous Hall effect in the studied structures is investigated; in particular, indications are obtained that there is the presence of a topological contribution at low temperatures.