Determination of the analytical and the nonanalytical part of the exchange interaction of InP and GaAs from polariton spectra in intermediate magnetic fields

摘要: The isotropic analytical exchange interaction ${\ensuremath{\Delta}}_{a}$ of GaAs and InP is determined to be 0.02\ifmmode\pm\else\textpm\fi{}0.01 0.04\ifmmode\pm\else\textpm\fi{}0.015 meV, respectively, for the two materials from a comparison theoretically generated experimentally transverse exciton energies oscillator strengths in magnetic fields up 20 T. calculation theoretical spectra based on recent intermediate-field theory including nonanalytical part interaction. experimental values are two-oscillator line-shape analysis ${\ensuremath{\sigma}}^{\ensuremath{-}}$,- ${\ensuremath{\sigma}}^{+}$-, $\ensuremath{\pi}$-polarized magnetoreflection spectra. A newly developed model describing exciton-free surface layer semiconductor by an exponentially decreasing damping contribution dielectric constant shown improve strongly quality fit. This improvement achieved without increasing number fitting parameters as compared older using finite thickness with infinite damping. From similar longitudinal-transverse mixed-mode which found $\ensuremath{\sigma}$ polarization Voigt configuration ($\stackrel{\ensuremath{\rightarrow}}{\mathrm{k}}\ensuremath{\perp}\stackrel{\ensuremath{\rightarrow}}{\mathrm{H}}$) size ${\ensuremath{\Delta}}_{\mathrm{LT}}$ 0.08\ifmmode\pm\else\textpm\fi{}0.02 meV. For upper limit ${\ensuremath{\Delta}}_{\mathrm{LT}}l~0.1$ meV derived.