Far-Infrared Magneto-Optical Absorption of Vertically Aligned Double Dot Array System

Abstract

We propose the optical control of the coupling between vertically aligned double dots. The coupling of the dots depends on the distance between the double dots and affects the strength of the electron-electron interaction in the dots. For this purpose, we fabricated a vertically aligned double dot array using a modulation-doped GaAs/AlGaAs single quantum well with two interfaces. Far-infrared magneto-optical absorption measurements of the double dot array system were carried out under photoexcitation. We observed a peak shift of the electron transition only in a dot located near the top interface. The peak shift includes the change in the coupling as well as the change in the confinement potential by the photoexcitation. This is evidence of the potential modulation by light which changes the coupling between the two dots. This indicates the possibility of the optical control of the coupling.