Multiphysics Simulation of Plasmonic Photoconductive Devices using Discontinuous Galerkin Methods

Abstract

Plasmonic nanostructures significantly improve the performance of photoconductive devices (PCDs) in generating terahertz radiation. However, they are geometrically intricate and result in complicated electromagnetic (EM) field and carrier interactions under a bias voltage and upon excitation by an optical EM wave. These lead to new challenges in simulations of plasmonic PCDs, which cannot be addressed by existing numerical frameworks. In this work, a multiphysics framework making use of discontinuous Galerkin (DG) methods is developed to address these challenges. The operation of the PCD is analyzed in stationary and transient states, which are described by coupled systems of the Poisson and stationary drift-diffusion (DD) equations and the time-dependent Maxwell and DD equations, respectively. Both systems are discretized using DG schemes. The nonlinearity of the stationary system is accounted for using the Gummel iterative method while the nonlinear coupling between the time-dependent Maxwell and DD equations is tackled during time integration. The DG-based discretization and the explicit time marching help in handling space and time characteristic scales that are associated with different physical processes and differ by several orders of magnitude. The accuracy and applicability of the resulting multiphysics framework are demonstrated via simulations of conventional and plasmonic PCDs.

References in corpus (4)

• Enhancement of Terahertz Photoconductive Antennas and Photomixers Operation by Optical Nanoantennas
• Computing optimal interfacial structure of modulated phases
• Steady-state Simulation of Semiconductor Devices using Discontinuous Galerkin Methods
• Numerical algorithms based on Galerkin methods for the modeling of reactive interfaces in photoelectrochemical (PEC) solar cells

Cited by in corpus (7)

• A Memory-efficient Implementation of Perfectly Matched Layer with Smoothly-varying Coefficients in Discontinuous Galerkin Time-Domain Method
• A hybridizable discontinuous Galerkin method for simulation of electrostatic problems with floating potential conductors
• Analysis of Screening Effects on Terahertz Photoconductive Devices using a Fully-Coupled Multiphysics Approach
• Efficient Discontinuous Galerkin Scheme for Analyzing Nanostructured Photoconductive Devices
• A Coupled Hybridizable Discontinuous Galerkin and Boundary Integral Method for Analyzing Electromagnetic Scattering
• Calculation of Photocarrier Generation from Optical Absorption for Time-domain Simulation of Optoelectronic Devices
• Multiphysics Modeling on Photoconductive Antennas for Terahertz Applications