Heterostructure interface effects on the far-infrared magneto-optical spectra of InAs/Gasb quantum wells

The electronic and optical properties of InAs GaSb heterostructures depend on the type of bonding at the interface, InSb bonds or GaAs bonds. We have studied cyclotron resonance (CR) in the far-infrared on two samples, each consisting of a single 30 nm InAs quantum well surrounded by thick GaSb barriers. The only intended difference between the samples is the interface bonding type, Ga-As bonds and In-Sb bonds. The CR for the sample with Ga As interface bonds shows two lines whose positions are determined by nonparabolicity effects, whereas the sample with In Sb bonds shows multiple lilies due to strong cross-interface coupling between the InAs conduction band Landau levels (LLs) and the valence band LLs in GaSb. We find that the CR is a sensitive probe of interface bonding type for Such structures. (C) 2002 Elsevier Science B.V. All rights reserved.