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arXiv · 2410.10331

Enhanced TM-Mode 3D Coupled Wave Theory for Photonic Crystal Surface-Emitting Terahertz Quantum Cascade Lasers

Mingxi Chen·Tsung-Tse Lin·Li Wang·Hideki Hirayama·Chiko Otani
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Abstract

In this study, we propose and develop an enhanced three-dimensional coupled wave theory (3D CWT) to investigate the optical field behavior in photonic crystal surface-emitting terahertz quantum cascade lasers (THz-QCLs). By incorporating an effective permittivity enhancement (EP) model and a self-consistent iteration (SCI) method, we successfully address the numerical dispersion issues encountered in analytical methods when dealing with metallic waveguide structures. The results demonstrate that the EP and SCI-enhanced 3D TM mode CWT achieves computational accuracy comparable to traditional numerical simulation methods such as finite-difference time-domain (FDTD), while significantly reducing the required computational resources, including time and memory, to just tens of minutes. Moreover, this method provides a clear physical insight, revealing the reasons behind the current low extraction efficiency in surface-emitting THz-QCLs. Our study showcases the potential of the EP and SCI-enhanced 3D CWT as a powerful simulation tool in the research of photonic crystal surface-emitting lasers, offering a new theoretical foundation and optimization direction for future laser designs.

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Mingxi Chen, Tsung-Tse Lin, Li Wang, Hideki Hirayama, Chiko Otani. 2024-10-14. Enhanced TM-Mode 3D Coupled Wave Theory for Photonic Crystal Surface-Emitting Terahertz Quantum Cascade Lasers. https://doi.org/10.1364/josab.563319

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