Dynamically tunable implementation of electromagnetically induced transparency with two coupling graphene-nanostrips in terahertz region

• Published in: Optics communications Vol. 411; pp. 48 - 52
• Main Authors: Shu, Chang, Chen, Qing-Guo, Mei, Jin-Shuo, Yin, Jing-Hua
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.03.2018
• Subjects: Active controlling; Electromagnetically induced transparency; Terahertz graphene metamaterials; Tunable group delay; Active controlling; Tunable group delay; Electromagnetically induced transparency; Terahertz graphene metamaterials
• ISSN: 0030-4018; 1873-0310
• DOI: 10.1016/j.optcom.2017.10.069

In this paper, we numerically demonstrated a dynamically tunable implementation of electromagnetically induced transparency (EIT) response with two coupling graphene-nanostrips in terahertz region. Compared to the metal-based structures or separated graphene structures, the Fermi energies of proposed two coupling graphene-nanostrips can be independently tuned by changing bias voltage between the metallic pads and substrate, the EIT window which appears from the near-field coupling between two resonators can be dynamically tuned without reoptimizing and refabricating the structures. As a result, the EIT window has a significant tunable capacity which can realize a higher frequency modulation depth and control the amplitude of transmission peak at a fixed frequency; moreover, the group delay of transmission peak at a fixed frequency with the amplitude of over 0.95 could be dynamically tuned. These results would exhibit potential applications in modulators and tunable slow light devices. •A tunable EIT structure with two coupling graphene-nanostrips is proposed.•EIT structure can realize a higher frequency modulation depth.•The amplitude of transmission peak at a fixed frequency can be controlled.•The group delay of transmission peak at a fixed frequency could be tuned.