BET3D - March-on-in-Time: Boundary Element Time-Domain Domain-Decomposition Methods

Modelling almost entirely replaced prototyping as a design methodology. In electromagnetics and optics, it has played a central role in the rapid development of communication and imaging, with applications in medicine, security, and energy. New technological requirements have always been met by breakthroughs in modelling.

Advances in TeraHertz technology have driven researchers to consider systems that are highly non-linear and strongly radiating. Modelling these systems requires methods that are based on time-stepping, and that can accurately describe unbounded regions. These requirements can only be met by time-domain boundary element methods (TD-BEMs). The use of other methods such as the finite element method, the method of moments, or the finite difference time-domain method – if at all applicable – results in unacceptable computational costs, and large errors in dispersion and radiation characteristics.

Unfortunately, TD-BEMs are not nearly as mature as other methods. They lack the ability to model all but the simplest systems. Attempts to use TD-BEMs to model realistic devices containing multiple materials, ports, coatings, or two-dimensional materials like graphene lead to instabilities, rendering the result of simulations completely useless. This state of affairs has persisted for over 50 years but has become an urgent problem now. BET3D will aggressively accelerate the development of the time-domain boundary element method into a method that can model highly non-linear, strongly radiating systems and that unlocks the capability to model emerging technologies in THz communications and imaging, and beyond.

As part of the benchmarking and validation for this project, we will model the generation of THz radiation by an array of graphene resonant tunnelling diode oscillators, including feeds, ports, packaging, and antenna structure. The results of BET3D will enable modelling of non-linear, radiating systems, also in acoustics, elastodynamics, and fluid dynamics.

RTD source of THz radiation

The type of devices BET3D targets: non-linear sources and sensors, comprising multiple materials, potentially including 2D membranes such as graphene, and strongly radiating into their environement.