The element level time domain (ELTD) method for the analysis of nano-optical systems: I. Nondispersive media

► A 3-dimensional time domain Maxwell solver on tetrahedral grids is studied. ► Its suitability for the numerical analysis of nano-optical devices is investigated. ► The theoretical details and its implementation as a computer code are introduced. ► The convergence behavior and stability conditions are examined. ► Through the analysis of analytically solvable problems the method is benchmarked.