Optimization of a Graphene-Based Optical Switch Structure for Achieving Fast Switching

Graphene-based optical switches are considered an ideal choice for designing electro-optical logic devices due to their unique features, such as nanoscale dimensions, low power consumption, high contrast ratio, wide bandwidth, and favorable operational speed. In these structures, the high excitability of electrons in graphene enhances switching speed, while the use of surface plasmons enables miniaturization and the propagation of waves at shorter wavelengths. Furthermore, graphene's ability to transmit surface plasmons across a broad frequency range expands the switch's operational scope. In this study, a graphene-based optical switch was designed, and the effects of varying parameters on its performance were analyzed. Results demonstrate that optimizing the structure's dimensions achieves a high extinction ratio, fast switching speed, and low energy consumption. Minor adjustments to graphene's chemical potential induce significant shifts in resonance frequency and modulation depth, highlighting the structure's high sensitivity to electric fields. Additionally, a Y-shaped switch design with dual waveguiding paths enables control over the propagation direction of surface plasmons via electrical bias adjustments. This symmetric structure comprises two equal-width arms, where the modulation of graphene's surface conductivity determines the wave transmission path. The switch's efficient performance in on/off states, characterized by a high transmission ratio and significant modulation depth, confirms the design's quality. These features, combined with the structure's subwavelength dimensions (smaller than the incident wavelength), facilitate the implementation of efficient logic gates with advanced digital capabilities.

کلیدواژه ها:

Optical switches ، Fast switching ، Surface plasmons ، Graphene