Band-gap tuning by impurity-free vacancy disordering was investigated in C and Zn p-doped laser structures. The Zn diffused during annealing and thus only C-doped material exhibited laser activity. After annealing, the threshold current densities rose from 225 to 255A/cm2; due to an increase in the transparency current. The gain constant of the quantum wells remained constant.

S.G.Ayling, A.C.Bryce, I.Gontijo, J.H.Marsh, J.S.Roberts: Semiconductor Science and Technology, 1994, 9[11], 2149-51