Spectroscopy of non-radiative recombination centers in quantum wells by two-wavelength excited photoluminescence

Nonradiative recombination centers in Si-doped GaAs/AlxGa1-xAs and GaN/In(y )G(1-y)N quantum well (QW) structures were studied by the two-wavelength ex cited photoluminescence technique. For the former, a pair of trap centers w as found in outer Al0.4Ga0.6As barrier layers: one of the pair is attribute d to be induced by the diffusion of Si atoms from neighboring Al-0.2 Ga-0.8 As barrier layers. In case of GaN/InyGa1-yN, a distribution of traps was d etected only inside the GaN layer, which is consistent with previous report s including the yellow luminescent band. (C) 2000 Elsevier Science B.V. All rights reserved.