Воздействие импульсов эксимерного лазера на светоизлучающие InGaAs/GaAs-структуры с (Ga, Mn)As-слоем

Abstract

It was studied the possibility of laser annealing modification of the properties of the (Ga,Mn)As layer located on the surface of a quantum-well InGaAs/GaAs structure, while retaining its radiative properties. The structures with four InGaAs/GaAs quantum wells (indium content was varied from 0.08 to 0.25), located at different distances from the (Ga,Mn)As layer, were fabricated by combining the methods of MOCVD-hydride epitaxy and pulsed laser deposition. The LPX-200 excimer laser pulse energy density was varied from 200 to 360 mJ/cm2, and the depth of laser action was determined from the change in the photoluminescence spectra of the quantum wells. In describing the results obtained, a model of the laser annealing process was used, based on solving the problem of heat propagation in a one-dimensional GaAs system, taking into account the (Ga,Mn)As layer on the surface. Changes in the structural and galvanomagnetic properties of the samples as a result of laser irradiation were analyzed. It is shown that as a result of pulsed laser action at a laser energy density range of 250 - 300 mJ/cm2, it is possible to preserve the emissive properties of the active region (InGaAs/GaAs quantum well) located at a distance of 10 - 12 nm from the (Ga,Mn)As layer and modify ferromagnetic properties of the semiconductor (Ga,Mn)As, namely: to increase the temperature of the ferromagnet-paramagnetic phase transition to values of at least 120 K. The results obtained are promising for the development of technology for devices of spin optoelectronics.