ELECTRONIC STRUCTURE AND BAND BENDING OF MODULATION-DOPED GaAs/Alx Ga1-xAs SYMMETRIC AND ASYMMETRIC DOUBLE QUANTUM WELLS UNDER AN APPLIED ELECTRIC FIELD

In this study, we have calculated theoretically the effects of the electric field and doping concentration on the sub-band energies, the electron population, and total charge density in modulation-doped symmetric and asymmetric GaAs/Al0.33Ga0.67As double quantum wells. Electronic properties of the system are determined by the solving the Schrödinger and Poisson equations self-consistently in the effective-mass approximation. The application of an electric field in the growth direction of the system causes a polarization of the carrier distribution and shifts the sub-band energies, which may be used to control and modulate intensity output devices. In an asymmetric double-quantum-well structure, the effects mentioned above appear more clearly.