Persistent photoconductivity in thin epitaxial GaAs Available to Purchase

We have studied persistent photoconductivity in thin epitaxial GaAs. The dependence of the persistent photoconductivity on photon dose was studied. At high fluences, a decay component was also observed. The temperature dependence of the persistence was determined. All the data are qualitatively well understood in terms of a macroscopic barrier model of persistent photoconductivity. At low photon fluences, excellent quantitative agreement between theory and data is obtained. At high fluences, the persistent photoconductivity is observed to approach a saturation value. The saturation is attributed to the barrier height reduction by the forward biasing effect of the separated charge. Eventually, the barrier height is reduced to the point that electrons spill over the barrier and prevent any further separation.