Optical generation of spatially separated electron and hole gases in intrinsic GaAs/Al(x)G(1-x)As double quantum wells - art. no. 113302

We show that optical excitation of a wide GaAs quantum well, which is locat ed close to the sample surface, can give rise to the creation of a high-den sity two-dimensional hole gas in the well. Based on this mechanism, we pres ent a double quantum well structure in which spatially separated electron a nd hole gases are optically created at close proximity (similar to 20 nm). We demonstrate how the density of each gas can be independently controlled by the intensity of the exciting lasers.