Characterization of spectral features of cavity modes in one-dimensional graphene-based photonic crystal structures

In this study, a numerical approach based on the transfer-matrix method (TMM) is employed to investigate, the optical features of an ultra-high-quality factor (Q-factor). The cavity is formed by incorporating a defect layer in a one-dimensional graphene photonic crystal (1D-GPC) structure. The cavity modes are identified, and the dependency of their spectral characteristics on the opto-geometrical parameters of the structure and the chemical potential (mu(C)) of graphene are investigated in detail. Our simulation results indicate that a tunable ultra-high Q-factor is attainable with the proposed cavity device. It is shown that the eigenfrequencies of the cavity modes vary in similar way versus the considered parameters. While, their Q-factors exhibit some differences in their changes with the thicknesses of the material layers. We have also noticed that the proposed cavity exhibits a cavity mode whose Q-factor increases exponentially with the number of layers in the distributed Bragg reflectors and with the graphene chemical potential. The observed tunable features of such kind of high Q-factor cavity make it an ideal candidate for the realization of ultrasmall tunable narrowband filters, sensing devices, and low-threshold lasers.

Automated summary

This study investigates the optical features of an ultra-high quality factor cavity using a numerical approach based on the transfer-matrix method. The results show that a tunable ultra-high Q-factor is achievable by adjusting the structural parameters and graphene chemical potential. The observed tunable features of this high Q-factor cavity make it an ideal candidate for ultrasmall tunable narrowband filters and sensing devices.