Free-electron tuning of optical properties of defect modes in semiconducting superlattices

We present numerical results for the optical response of tunable one-dimensional photonic crystals. Two different (monolithic) superlattices (SL) where studied: InSb/air and Si/air. We explore the tuning of a defect state as a function of the temperature and of the donor concentration. The numerical calculations were performed using a realistic model for the dielectric constant that takes into account the dispersion and absorption due to electrons, holes and phonons. In order to lessen absorptive effects, we have optimized the structure so as to achieve strong sensitivity of the defect state tuning.