T.F. Kuech, M.A. Tischler, et al.
Journal of Crystal Growth
Using a novel time-resolved optical photoluminescence imaging technique, analogous to the electrical Haynes-Shockley experiment, we have measured room-temperature minority-carrier transport in a series of "surface- free" GaAs/Al0.3Ga0.7As double heterostructures. These measurements are only possible in "surface-free" samples in which the band-to-band radiative recombination lifetimes are long-here up to 2.5 μs. We find minority-carrier transport to be "diffusive", with diffusion lengths of up to ∼140 μm. We also find transport in thick (≳1 μm) structures to be mediated by hole-dominated ambipolar diffusion, whereas for thinner structures a transition from ambipolar to free-electron-dominated diffusion is observed. These results demonstrate that our heterostructures become effectively modulation doped for GaAs thicknesses ≲1 μm.
T.F. Kuech, M.A. Tischler, et al.
Journal of Crystal Growth
S.S. Lau, W.X. Chen, et al.
Applied Physics Letters
L.C. Wang, X.Z. Wang, et al.
Journal of Applied Physics
D.J. Wolford, J.A. Bradley, et al.
ICDS 1984