A wide range of software now exists for the design and simulation of integrated optoelectronic components, especially for finding modes and describing propagation. The sophistication and high performance specifications of many devices mean that techniques must typically not only provide accurate vector results, or at least a reliable error estimate, but also be able to deal with multi-physics, multi-scale problems, intricate materials properties and arbitrary geometries. The design process also demands consideration of process variation and system optimisation issues. Time domain numerical techniques such as FDTD and TLM have come to the forefront in recent years, driven by their flexibility, adaptability and compatibility with parallel computing techniques. Nevertheless much present day simulation and design work involves approximations and an automated all-in-one design tool suitable for every purpose is still far from being realised.
In this invited paper we will review features of integrated optics design applications, point out some of the features of emerging technologies that mitigate against the general applicability of present-day software tools, and show how substantial benefit can still to be gained from developing bespoke novel algorithms or exploiting an appreciation of the physical mechanisms underpinning the behaviour of particular components and systems.