Action of Excimer Laser Pulses on Light-Emitting InGaAs/GaAs Structures with a (Ga,Mn)As-Layer

The possibility of modifying the properties of a (Ga,Mn)As layer on the surface of a quantum-size InGaAs/GaAs-structure by laser annealing with the conservation of its emitting properties is studied. To perform these studies by a combination of the methods of MOC-hydride epitaxy and pulsed laser deposition, the structures have been prepared with four quantum wells InGaAs/GaAs (indium contents from 0.08 to 0.25) located at various distances from the (Ga,Mn)As layer. The radiation energy density of an LPX-200 pulsed excimer laser was varied during the experiments from 200 to 360 mJ/cm 2 , and the depth of the laser action was determined from the changes in the photoluminescence spectra of the quantum wells. The results are described using the laser annealing model based on the solution of the problem of heat propagation in a one-dimensional GaAs system, taking into account a (Ga,Mn)As layer on the surface. The changes in the structural and galvanomagnetic properties of the samples under action of laser irradiation are analyzed. It is shown that the pulsed laser irradiation with the laser radiation energy density 250–300 mJ/cm 2 enable one to conserve the emitting properties of the active region (quantum wells InGaAs/GaAs) disposed at the distances 10–12 nm from the (Ga,Mn)As layer and to modify the ferromagnetic properties of the (Ga,Mn)As semiconductor, namely, to increase the ferromagnet–paramagnet phase transition temperature to values no lower than 120 K. The results are promising for the development of the technology of devices of spin optoelectronics.