Device package

One of the central elements of the device package is the Device class, which can model a wide range of real-world devices. In the first tutorial of this section, a silicon nanowire gate-all-around field-effect transistor (GAAFET) is implemented as a QTCAD Device object; the Schrödinger and Poisson equations are then solved successsively in this system over a static mesh. In the second tutorial, we explain how to use adaptive meshing for more robust solutions of the non-linear Poisson equation at cryogenic temperature. In the third tutorial, we explain how to account for user-defined parasistic background volume and surface charge densities when solving the non-linear Poisson equation. In the fourth tutorial, the Schrödinger equation is solved in a specific region of a device after solving the non-linear Poisson equation with an adaptive mesh. In the fifth tutorial, the Schrödinger equation is solved in a quantum dot. In the sixth tutorial, the alignment of bands in heterostructures is explained. In the seventh tutorial, the output of QTCAD simulations (e.g. electric potential and wavefunctions) are visualized in ParaView. In the eighth tutorial, the Schrödinger and Poisson equations are solved self-consistently for a 1D metal–oxide–semiconductor capacitor. In the ninth tutorial, we get the band structure for holes confined to a 1D particle-in-a-box-like quantum well. In the tenth tutorial, we look at the effects of spin–orbit coupling for holes subject to a constant magnetic field. In the eleventh tutorial, we demonstrate how strain can be used to modify the character of the ground-state hole wavefunction. In the twelfth tutorial, the eigenstates of an electron confined in silicon are found using a multi-valley effective-mass theory. In the thirteenth tutorial, the many-body problem is solved for the GAAFET studied in the first tutorial. In the fourteenth tutorial, a function is defined to produce Device objects for double quantum dots defined in a generic fully-depleted silicon-on-insulator (FD-SOI) geometry. We study tunnel coupling in such double-dot FD-SOI devices in tutorials fifteen and sixteen of this section and exchange coupling in tutorials seventeen and eighteen. Finally, in tutorial nineteen, we investigate how point charges can affect the quantum-dot energy spectrum in this same FD-SOI setting.