Enhancing Efficiency of Electromagnetic Simulation in Time Domain with Transformation Optics

Abstract

Featured Application: The main contribution of this work is to propose an electromagnetic finite-difference time-domain method that applies transformation optics for the generation of arbitrary non-uniform physical grids in a simulation system. This method can be applied to the simulation study of light interaction with sub-wavelength structures with efficiency.Abstract: With sub-wavelength scaled structures in a large system, the conventional finite-difference time-domain method can consume much computational resources since it includes both the spatial and temporal dimension in the scheme. In order to reduce the computational cost, we combine the novel methodology "transformation optics" in the simulation to map a physical coordinate with designated non-uniform grids to a uniform numerical coordinate. For a demonstration, the transmission spectrum through a sub-wavelength metallic aperture with one-dimensional and two-dimensional coordinate transformation is simulated, and compared with uniform-grid cases. We show that the proposed method is accurate, and the computational cost can be reduced remarkably to at most 5.31%, in comparison with the simulation of the finest uniform grids demonstrated. We are confident that it should be helpful to the simulation study in sub-wavelength optics due to its verified accuracy and efficiency.

A Thermopile Device with Subwavelength Structure by CMOS-MEMS Technology

“…In this study, various CMOS compatible thermopiles with subwavelength structures are fabricated in the standard 0.35 m CMOS-MEMS, which are numerically and experimentally investigated and reach agreement with response curves. The various subwavelength structures (SWSs) of photonic devices are analyzed by the finite-difference time-domain (FDTD) [13,14] method. Then, the thermopile with subwavelength structure (SWS) [15] is fabricated by the 0.35 µm 2P4M CMOS-MEMS process.…”

3D-Printing for Transformation Optics in Electromagnetic High-Frequency Lens Applications

“…This tool allows to transform any electromagnetic device into a different equivalent, having the same electromagnetic characteristics but with a different morphology. This has been the kickoff of many interesting applications [3][4][5], specially in electromagnetic high-frequency topologies [6,7]. One of the main applications of this tool is oriented to improve lens designs, such as simplifying their geometry and reducing their overall size [8][9][10].…”