A system of diffusion-type equations for transport in 3d confined structures is derived from the Boltzmann transport equation for charged particles. Transport takes places in confined structures and the scaling in the derivation of the diffusion equation is chosen so that transport and scattering occur in the longitudinal direction and the particles are confined in the two transversal directions. The result are two diffusion-type equations for the concentration and fluxes as functions of position in the longitudinal direction and energy. Entropy estimates are given. The transport coefficients depend on the geometry of the problem that is given by arbitrary harmonic confinement potentials. An important feature of this approach is that the coefficients in the resulting diffusion-type equations are calculated explicitly so that the six position and momentum dimensions of the original 3d Boltzmann equation are reduced to a 2d problem. Finally, numerical results are given and discussed. Applications of this work include the simulation of charge transport in nanowires, nanopores, ion channels, and similar structures. © 2011 International Press.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): KUK-I1-007-43
Acknowledgements: This work was supported by the FWF (Austrian Science Fund) project no. P20871-N13 and by theWWTF (Viennese Science and Technology Fund) project no. MA09-028. This publication is basedon work supported by award no. KUK-I1-007-43, funded by the King Abdullah University of Scienceand Technology (KAUST).This work was supported by National Science Foundation awards nos. DMS-0604986 and DMS-0757309.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.