Propagation characteristics of terahertz waves in graphene–microplasma photonic crystals

This study proposes a terahertz (THz) wave absorber structure based on one-dimensional photonic crystals incorporating graphene and microplasma. The propagation matrix method is employed to examine the influence of critical parameters, including incident angle, plasma thickness, electron density, collision frequency, and the number of photonic crystal periods, on the propagation of THz waves. Results reveal that larger incidence angles shift the absorption band to higher frequencies through Bragg reflection, while increasing plasma thickness generates additional low-frequency interference patterns due to Fabry–Pérot resonance. An appropriate collision frequency maximizes energy dissipation, and adding more periods strengthens and broadens the absorption range. These findings provide meaningful guidance for designing tunable, broadband THz absorbers.