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

Ungan F., Kasapoglu E., Sari H., Sokmen I.

SURFACE REVIEW AND LETTERS, vol.16, no.1, pp.105-110, 2009 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 16 Issue: 1
  • Publication Date: 2009
  • Doi Number: 10.1142/s0218625x09012366
  • Journal Name: SURFACE REVIEW AND LETTERS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.105-110
  • Keywords: Low-dimensional systems, double quantum well, COLLECTIVE MODES, TUNNELING TIMES, OSCILLATIONS, EXCITATIONS, PLASMONS
  • Dokuz Eylül University Affiliated: Yes

Abstract

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 Schrodinger 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.