Contribution of single InGaAs quantum wells to the guided mode dispersion of InGaAs GaAs AlGaAs waveguides: model and experimental results

The group index dispersion of TE and TM polarized modes in single quantum well InGaAs AlGaAs GaAs graded index separate confinement heterostructure waveguides was obtained by high resolution Fabry-Perot fringe spacing measurements. The TE mode data, over a 175 nm range below the quantum well band gap, were compared with model computations of guided mode dispersion utilizing current empirical equations for the index dispersion of Al(sub x)Ga(sub 1-x) and GaAs, and various phenomenological equations for the TE index dispersion of the InGaAs quantum well. A satisfactory fit was observed when the quantum well was modeled as a two-dimensional set of equal strength oscillators with a constant density of states, plus a single 1S excitonic level.