Conformal Mapping Design Tools for Coaxial Couplers with Complex Cross Section

Numerical conformal mapping is exploited as a simple, accurate, and efficient tool for the analysis and design of coaxial waveguides and couplers of complex cross section. An implementation based on the Schwarz-Christoffel Toolbox, a public-domain MATLAB package, is applied to slotted coaxial cables and to symmetrical coaxial couplers, with circular or polygonal inner conductors and external shields. The effect of metallic diaphragms of arbitrary thickness, partially separating the inner conductors, is also easily taken into account. The proposed technique is validated against the results of the finite-element method, showing excellent agreement at a fraction of the computational cost, and is also extended to the case of nonsymmetrical couplers, providing the designer with important additional degrees of freedom

Modeling of single-mode high-power VCSEL arrays

In this work we investigate different architectures to realize a single-mode VCSEL array for high power applications. This is done by simulating a large active-area VCSEL with either a metallic or a grating-relief-based patterning at the outcoupling aperture. The investigated designs are compared, highlighting possible strategies to improve the fiber coupling by improving the far field (FF) profile. This contribution also presents a satisfactory match between the simulations and the FF experimental data obtained from the measurements of a VCSEL array structure

Modeling the Conductor Losses of Thick Multiconductor Coplanar Waveguides and Striplines: A Conformal Mapping Approach

A conformal-mapping approach to model the skin-effect conductor losses of thick multiconductor coplanar waveguides and multiconductor coplanar strips is proposed. The model allows for arbitrary strip or slot number and widths and is accurate for conductor thicknesses up to around 40% of the minimum strip and slot width. Examples are presented to demonstrate the accuracy of the approach when compared to the results from a finite-element method numerical code

DETAILED DRIFT DIFFUSION MODEL FOR THE ANALYSIS AND DESIGN OF QUANTUM DOT SOLAR CELLS

We propose a model for the simulation of quantum dot solar cells, based on drift-diffusion transport equations coupled with detailed rate equations of the quantum dots. Preliminary validation against literature experimental data is presente