Infrared magnetooptic — A tool for the determination of the effective mass

Abstract

The analysis of the magnetooptical effects of heavily doped materials at the plasma edge yields the concentration dependence of the effective cyclotron mass. Therefore these experiments support the general diskussion about the nonparabolicity of a band, the position of the Fermi level at high degenerated semiconductors and the determination of the$E(\vec k)$ dispersion function. Experimental results of the magnetooptical determinedm ^* _c (N) function are compared with coresponding band structure calculations. A matrix calculation model, which describes the symmetrical magnetooptical transmission effects as well as the asymmetrical magnetooptical reflection effects of arbitrary successions of coherent films and incoherent substrates consitently, is used to determine free carrier density profilesN (z) of inhomogeneously doped semiconductors non-destructively. This application of the matrix formalism requires the knowledge of them ^* (N)-function. The influence of the effective cyclotron mass on thedifferential magnetooptical interference structures caused by buried density profiles is discussed.