The effects of free-carrier-induced shift and broadening on the carrier distribution function are studied considering different extreme cases for carrier statistics (Fermi–Dirac and random carrier distributions) as well as quantum dot (QD) ensemble inhomogeneity and state separation using a Monte Carlo model. Using this model, we show that the dominant factor determining the carrier distribution function is the free carrier effects and not the choice of carrier statistics. By using empirical values of the free-carrier-induced shift and broadening, good agreement is obtained with experimental data of QD materials obtained under electrical injection for both extreme cases of carrier statistics.

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We present a Monte Carlo model that simulates the gain spectra of a QD laser material that empirically includes free-carrier effects. We compare simulation results of both Fermi–Dirac and random carrier populations, and compare them with experimental data. The free-carrier effects are highlighted as being more important than the choice of carrier statistics, and routes to improve this simple model are discussed.

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In this paper, a novel power UMOSFET_ACCUFET structure, based-on 6H-SiC, has been investigated. By varying the dimensions and doping concentrations of specific regions, we have obtained optimized electric field and on-resistance. Two approaches have been applied to the simple UMOSFET structure, both of which result in lower peak electric field in the device in the blocking state.