# CELES: CUDA-accelerated simulation of electromagnetic scattering by large ensembles of spheres

## TL;DR

CELES is a MATLAB toolbox that uses CUDA acceleration and advanced numerical techniques to efficiently simulate electromagnetic scattering by large ensembles of spherical particles on consumer hardware.

## Contribution

It introduces a GPU-accelerated MATLAB toolbox with novel preconditioning and lookup-table methods for large-scale light scattering simulations.

## Key findings

- Validated near- and far-field distributions against established MSTM code
- Achieved efficient simulations for ensembles exceeding 10^4 particles
- Demonstrated scalability to systems with 10^5 particles

## Abstract

CELES is a freely available MATLAB toolbox to simulate light scattering by many spherical particles. Aiming at high computational performance, CELES leverages block-diagonal preconditioning, a lookup-table approach to evaluate costly functions and massively parallel execution on NVIDIA graphics processing units using the CUDA computing platform. The combination of these techniques allows to efficiently address large electrodynamic problems ($>10^4$ scatterers) on inexpensive consumer hardware. In this paper, we validate near- and far-field distributions against the well-established multi-sphere $T$-matrix (MSTM) code and discuss the convergence behavior for ensembles of different sizes, including an exemplary system comprising $10^5$ particles.