Beschreibung:
<jats:p>A new type of slow-relaxation phenomena is found in low-temperature photoconductivity for undoped semi-insulating GaAs: Irradiation by secondary light subsequent to the primary-light irradiation induces a rapid increase followed by a gradual exponential decrease in photoconductivity. This phenomenon cannot be explained by conventional photoelectric fatigue, though these are similar to each other. A model is proposed to explain this phenomenon, involving a dynamical transition of carriers by primary- and secondary-light irradiation. This model is consistent with the results of annealing experiments for the phenomenon.</jats:p>