Model for Ultrafast Extrinsic Photoconductivity in Er-Doped GaAs
A model is constructed for extrinsic photoconductivity in GaAs heavily doped with Er and driven around 1550 nm. The model is based on internal photoionization of ErAs nanoparticles in the diameter range 2.0 to 2.5 nm, which occurs via a resonant, bound-to-continuum electron transition between the Γ-point in the atomic-like ErAs and the Γ-valley in the GaAs. The model is consistent with all experimental evidence to date, including sub-band absorption, photo-Hall measurements, 1550-nm pump-probe photocarrier lifetime, and THz power generation.
& Mirin, R.
(2016). Model for Ultrafast Extrinsic Photoconductivity in Er-Doped GaAs. International Conference on Infrared, Millimeter, and Terahertz Waves, IRMMW-THz.