Диодные гетероструктуры с ферромагнитным слоем (Ga, Mn)As

Abstract

The diode p-(Ga,Mn)As/n-InGaAs/n+-GaAs heterostructures, which differ in thickness (from 5 to 50 nm) of a diluted magnetic semiconductor (Ga,Mn)As layer, were fabricated and studied. We found the negative magnetoresistance effect, reaching 6–8% in a 3600 Oe magnetic field. The effect was conserved up to temperatures of 70–80 K and associated with a decrease in charge carrier scattering due to ferromagnetic ordering in the (Ga,Mn)As layer. The dependence of the magnetoresistance on the forward bias voltage is nonmonotonic with the maximum magnetoresistance and its observation voltage range depending on the (Ga,Mn)As layer thickness. The magnetic field dependences of the magnetoresistance have a hysteretic shape due to the influence of tensile stresses in the (Ga,Mn)As layer grown on top of the relaxed InGaAs material on the appearance of the magnetization component, perpendicular to the structure surface.