Efficient discontinuous Galerkin scheme for analyzing nanostructured photoconductive devices

Area of Science:

• Optoelectronics
• Computational Physics
• Nanotechnology

Background:

• Plasmonic nanostructures enhance optical-to-terahertz conversion efficiency in photoconductive devices (PCDs).
• Simulating nanostructured PCDs is computationally expensive due to multiphysics and complex geometries.
• Accurate modeling requires addressing multiple time and spatial scales.

Purpose of the Study:

• To develop an efficient simulation scheme for nanostructured PCDs.
• To reduce the computational cost associated with modeling these complex devices.
• To maintain accuracy in predicting terahertz photocurrent.

Main Methods:

• A discontinuous Galerkin (DG)-based unit-cell scheme was proposed.
• Two coupled systems of equations were used: Poisson/drift-diffusion for steady-state and Maxwell/drift-diffusion for transient stages.
• Potential-drop and periodic boundary conditions were implemented for bias voltage and fields/densities.

Main Results:

• The DG-based unit-cell scheme achieved high accuracy in predicting terahertz photocurrent.
• The proposed scheme significantly reduced computational cost compared to whole-device simulations.
• The method effectively models the coupled physical stages of nanostructured PCDs.

Conclusions:

• The DG-based unit-cell scheme offers an efficient and accurate approach for simulating nanostructured PCDs.
• This method simplifies the design and simulation of devices with improved optical-to-terahertz conversion.
• The findings contribute to advancing the development of terahertz technologies.