A rigorous numerical modeling of exciton electroabsorption in coupled multiple quantum wells modulators

In this paper an accurate model for calculation electroabsorption spectrum of CMQWS modulators is proposed. First, the electron and hole subband energy levels and their envelope wave functions are calculated using transfer matrix method (TMM). Next a variational method is used to obtain the exciton binding energy and its wave function. Then electroabsorption spectrum for TE and TM mode of input light is calculated considering band to band and excitonic transitions without any fitting parameter. The broadening of excitonic peak with phonon interaction, applied electric field, well width variation, temperature fluctuation and quasi bound life time is taken into account. Then, numerical results are presented. The results are in good agreement with experimental results reported.