Annegret Glitzky

An Electronic Model for Solar Cells Including Active Interfaces and Energy Resolved Defect Densities

We introduce an electronic model for solar cells taking into account heterostructures with active interfaces and energy resolved volume and interface trap densities. The model consists of continuity equations for electrons and holes with thermionic emission transfer conditions at the interface and of ODEs for the trap densities with energy level and spatial position as parameters, where the right-hand sides contain generation-recombination as well as ionization reactions. This system is coupled with a Poisson equation for the electrostatic potential. We show the thermodynamic correctness of the model and prove a priori estimates for the solutions to the evolution system. Moreover, existence and uniqueness of weak solutions of the problem are proven. For this purpose we solve a regularized problem and verify bounds of the corresponding solution not depending on the regularization level.

GLOBAL EXISTENCE RESULT FOR PAIR DIFFUSION MODELS

In this paper we prove a global existence result for pair diffusion models in two dimensions. Such models describe the transport of charged particles in semiconductor heterostructures. The underlying model equations are continuity equations for mobile and immobile species coupled with a nonlinear Poisson equation. The continuity equations for the mobile species are nonlinear parabolic PDEs involving drift, diffusion, and reaction terms; the corresponding equations for the immobile species are ODEs containing reaction terms only. Forced by applications to semiconductor technology, these equations have to be considered with nonsmooth data and kinetic coefficients additionally depending on the state variables.Our proof is based on regularizations, on a priori estimates which are obtained by estimates of the free energy and by Moser iteration, as well as on existence results for the regularized problems. These are obtained by applying the Banach fixed point theorem for the equations of the immobile species, a...

Systems Describing Electrothermal Effects with

We consider a coupled system of two elliptic PDEs, where the elliptic term in the first equation shares the properties of the

p(x)

p(x)

-Laplacian-like Structure for Discontinuous Variable Exponents

-Laplacian with discontinuous exponent, while in the second equation we have to deal with an a priori

Existence of Bounded Steady State Solutions to Spin-Polarized Drift-Diffusion Systems

L^1

Operation mechanism of high performance organic permeable base transistors with an insulated and perforated base electrode

term on the right-hand side. Such systems are suitable for the description of various electrothermal effects, in particular, those where the non-Ohmic behavior can change dramatically with respect to the spatial variable. We prove the existence of a weak solution under very weak assumptions on the data and also under general structural assumptions on the constitutive equations of the model. The main difficulty consists in the fact that we have to simultaneously overcome two obstacles---the discontinuous variable exponent and the

Hybrid Finite-Volume/Finite-Element Schemes for p(x)-Laplace Thermistor Models

L^1

OLEDs: light-emitting thin film thermistors revealing advanced self-heating effects

right-hand side of the heat equation. Our existence proof based on Galerkin approximation is highly constructive and therefore seems to be suitable also for numerical purposes.

Electro-thermal modeling of organic semiconductors describing negative differential resistance induced by self-heating

We study a stationary spin-polarized drift-diffusion model for semiconductor spintronic devices. This coupled system of continuity equations and a Poisson equation with mixed boundary conditions in all equations has to be considered in heterostructures. In 3D we prove the existence and boundedness of steady states. If the Dirichlet conditions are compatible or nearly compatible with thermodynamic equilibrium, the solution is unique. The same properties are obtained for a space discretized version of the problem: Using a Scharfetter–Gummel scheme on 3D boundary conforming Delaunay grids, we show existence, boundedness, and, for small applied voltages, the uniqueness of the discrete solution.