We grew a multiple quantum well GaAs/AlGaAs (100/200-Å) structure with alternating n(Si) and p(Be) ∂-doping layers1 in the middle of AlGaAs barriers with a 2-D doping density of 1×1013 cm−2 for both p-and n-dopants. The ∂-doping technique allows one to localize impurities on a lattice-constant length scale and introduce very high 2-D densities of Si and Be impurities in GaAs or AlGaAs. The ionized ∂-sheets of Si and Be ions generate localized alternating high electric fields inside the crystal with better uniformity than conventional doping techniques.2 It is known that the quantum-confined Stark effect by a perpendicular electric field induces large absorption changes at the band edge of multiple quantum well structures.3 We want to screen the built-in electric fields by photogenerated carriers without wires. The screening results in changes of absorption at the band edge of GaAs quantum well that are useful for nonlinear optical applications.
© 1989 Optical Society of AmericaPDF Article