Hybrid Graphene-Gold Nanorod Plasmonic System for Tunable Terahertz Notch Filters

This study explores the development of a highly tunable terahertz notch filter utilizing graphene nanoribbons integrated with gold nanorods on a silica substrate. The research leverages the plasmonic resonance properties of both graphene and gold to enhance the performance of the filter, especially for biomedical imaging and diagnostic applications. By employing a finite-difference time-domain method, the interaction between localized surface plasmon resonance in gold nanorods and plasmonic guided modes in graphene was investigated. The optimized results obtained from this study indicate that incorporating gold nanorods causes a blueshift in the resonance frequency, enhancing the efficiency of the filter. Additionally, tuning the graphene's Fermi level through an applied voltage enables dynamic control of the filter’s performance, making it suitable for adaptive biomedical applications. The findings suggest that this hybrid plasmonic system offers potential for advanced optical biosensors.