Software for self-consistent quantum-electrostatics

Static Modeling – NXT, GRE. We will set up a precisely calibrated model of the heterostructures to be studied during the project. This includes a self-consistent treatment of the Poisson-quantum problem that will capture the large energy physics of the devices (eV to meV) even in the presence of strong non-linearities in the density of states and/or sharp interfaces such as in the p-n junctions. For this purpose, we will develop an integrated 3D Poisson solver and 3D quantum solver capable of handling out-of-equilibrium situations. The corresponding software will be integrated into NXT software stack and transferred to the other experimental teams to be used at the device design level. A particularly challenging algorithm is the self-consistent solver that links the Poisson solver with the quantum solver. While this is a manageable task in 1D or 2D simulations (already handled by NXT commercial software), the number of eigenvectors required for a 3D simulation can become very huge because a lot of them contribute to the quantum density in the two-dimensional electron gas. Innovative approaches both in the modelling techniques (combining real space with eigenmode space, coarse-graining approach) and in the numerical methods (e.g. eigenvalue solvers, adaptive grid) will be developed to rapidly and accurately predict the electronic properties of the devices.