Studies of far-infrared magneto-photoconductivity of D − centers in GaAs/Al xGa 1− xAs multiple quantum wells

Abstract

We present magneto-photoconductivity studies on GaAs/Al 0.3Ga 0.7As multiple quantum wells selectively doped with Si donors in the center of the wells and in the barrier layers. Under extra illumination of an He–Ne laser, dramatic results of the D − centers were observed as a function of the electron density. A band-bending model associated with a “barrier D − center” configuration was used to analyze the evolution of the binding energy of the spin-singlet D − transition and magnetic vaporization.