Disorder of an AlxGa1−xAs-GaAs superlattice by donor diffusion

Abstract
The Si impurity is diffused (850 °C, 10 h, xj ∼2.4 μm) into 2.4 μm of AlxGa1−xAs‐GaAs (x≳0.6) superlattice (barrier LB ≊320 Å, quantum well Lz ≊280 Å) and disorders it into bulk‐crystal AlxGa1‐xAs (x′≳0.32). The as‐grown infrared gap superlattice is converted selectively to red gap bulk crystal and, where undiffused and not disordered, is still capable of continuous 300‐K photopumped laser operation at a threshold of 4×103 W/cm2 (or Jeq ∼1.7×103 A/cm2, 5145 Å pump photon).