Laser irradiation of GaAsGaAlAs multi-quantum well structure

We have studied the effects produced by laser irradiation with 355 nm photons on a heterostructure made of three independent View the MathML source quantum wells. By comparing the luminescence of the three quantum wells before and after the laser irradiation for different durations and fluence values one could determine if the structure of each quantum well has been altered or not. Then we achieved complementary observations of the irradiated multi-quantum wells structures, using both scanning and transmission electron microscopy. We came to the conclusion that the alteration of the multi-quantum wells structure results from two main consequences of the sample pulsed laser heating: the formation of an altered layer which accompanies the pulsed laser sputtering process and the thermal diffusion process.