412 research outputs found
Drift-diffusion models for the simulation of a graphene field effect transistor
AbstractA field effect transistor having the active area made of monolayer graphene is simulated by a drift-diffusion model coupled with the Poisson equation. The adopted geometry, already proposed in (Nastasi and Romano in IEEE Trans. Electron. Devices 68:4729–4734, 2021, 10.1109/TED.2021.3096492), gives a good current-ON/current-OFF ratio as it is evident in the simulations. In this paper, we compare the numerical simulations of the standard (non-degenerate) drift-diffusion model, that includes the Einstein diffusion coefficient, with the degenerate case
Comparing kinetic and hydrodynamical models for electron transport in monolayer graphene
The aim of this work is to compare, in monolayer graphene, solutions of the
electron Boltzmann equation, obtained with a discontinuous Galerkin method, with those
of a hydrodynamical model based on the Maximum Entropy Principle
Pauli principle and the Monte Carlo method for charge transport in graphene
An attempt to include the Pauli principle in the Monte Carlo method by also acting on the free-flight step and
not only at the end of each collision is investigated. The charge transport in suspended monolayer graphene is
considered as a test case. The results are compared with those obtained with the standard ensemble Monte Carlo
technique and with the updated direct simulation Monte Carlo algorithm which is able to correctly handle with
Pauli’s principle. The physical aspects of the investigated approach are analyzed as well
Multiscale analysis of tunnel ventilation flows and fires
Presentazione a 11èmes journées du GDR Incendie, CSTB - Champs sur Marne, Paris (Fr), 17th -18th June 201
Relation between growth dynamics and diffusional limitations in Saccharomyces cerevisiae cells growing as entrapped in insolubilized gel
Flow-cytometric analysis was employed to investigate growth dynamics of a yeast cell population immobilised in an insolubilised gelatin gel by means of the quantitative determination of the average protein content per cell. This analysis was carried out on both the immobilised cell population considered as a whole and the subpopulations colonising the gelatin matrix at different depths. The results show that growth of the gelatin-immobilised yeast population was affected by the existence of a gradient of nutrient concentrations through the matrix and are in agreement with the unsteady-state diffusion model employed for the description of glucose transfer in the gel
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