Compositional superlattices are generally classified into two different types, depending of the relative position of the band edges of the two component materials. In type-I superlattices the two energy gaps overlap. In type-II superlattices, such as InAs-GaSb on the other hand, the valence band top of one material (GaSb) lies higher in energy than the conduction band bottom of the other one. Charge transfer across the interfaces is then to be expected, and, therefore, the possibility of obtaining a metallic system by combining two semiconductors. The many-band envelope function approach to the superlattice band structure is equally accurate for type-I or type-II systems. However, the main motivation for this work is the electronic structure and the semiconductor-semimetal transition in InAs-GaSb, and only results for this system are presented.
 

Proceedings of the International School of Physics 'Enrico Fermi'; Course LXXXIX. Highlights of Condensed-Matter Theory Editor(s): Bassani, F.; Fumi, F.; Tosi, M.P. Amsterdam, Netherlands: North-Holland, 1985. p.225-36 of xviii+916 pp. 23 refs. Conference: Varenna, Italy, 28 June-16 July 1983 ISBN: 0-444-86976-X.