High pressure and high magnetic field studies of the two-dimensional electron gas at a CdTe/InSb interface

• Published in: Surface science 1990-04, Vol.229 (1), p.428-432
• Main Authors: Alikacem, M., Leadbeater, M.L., Maude, D.K., Davies, M., Eaves, L., Heath, M., Dmowski, L., Portal, J.C., Ashenford, D., Lunn, B.
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Physics
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/0039-6028(90)90923-V

The Shubnikov-de Haas effect is investigated in single heterostructures of CdTe grown on (100) p-type InSb substrates by molecular beam epitaxy. At least six electrically-quantised subbands are occupied at atmospheric pressure, corresponding to a total sheet carrier density of 6.7 × 10 12 cm −2. The application of hydrostatic pressure up to 15 kbar reduces this to 2.6 × 10 12 cm −2and increases the mobility by a factor of two, indicating that the Fermi energy of the electron gas is pinned at donor-like interface states. The energies of the subbands are calculated using a two-band model. Magneto-oscillations due to subband depopulation in the B ∥ configuration are also studied.