Landau-level lifetimes are determined from saturation cyclotron resonance measurements on an InAs/GaSb double heterojunction using a picosecond far-infrared free-electron laser. Strong nonparabolicity of the conduction band truncates the equidistant Landau-level ladder, and saturation is achieved at all wavelengths. The Landau-level lifetimes show minima at N(Latin small letter h with stroke sign)?c=(Latin small letter h with stroke sign)?LO, a direct observation of the magnetophonon effect. Observed picosecond lifetimes are due to LO-phonon emission which dominates electron-electron scattering at the magnetophonon resonance condition.
|Number of pages||4|
|Journal||Physical Review B: Condensed Matter and Materials Physics|
|Publication status||Published - 15 Jun 1996|