CYCLOTRON-RESONANCE SUBMILLIMETER LASER-EMISSION IN HOT HOLE LANDAU-LEVEL SYSTEM IN UNIAXIALLY STRESSED P-GERMANIUM

The results of experimental and theoretical studies of hole distributi on function and cyclotron resonance (CR) laser emission processes in u niaxially stressed p-Ge in strong crossed E perpendicular-to H fields are presented. The CR emission spectra were studied for various orient ations of E and H fields with respect to the crystallographic axes of the p-Ge crystal. A complicated structure of CR emission spectra (inst ead of a single line without stress) was found to arise in stressed cr ystals, corresponding to transitions between different pairs of light hole Landau levels. A considerable effect of quantum deformation of th e lower light hole Landau levels due to interaction and mixing of ligh t and heavy hole states on emission spectra was found, resulting in st rong broadening and shift with the stress of an emission line, corresp onding to (n = 2) --> (n = 1) transitions. The transitions were shown to dominate in CR emission spectra for stress larger than 400 bar. Num erical calculations of hole lifetimes and distribution function in uni axially stressed Ge based on the quantum model of carrier dynamics in strong crossed E and H fields were carried out, taking into account th e optical phonon and ionized impurity scattering processes. The result s of the calculations allowed us to identify the observed CR transitio ns.