Abstract
Active photonics based on graphene has attracted wide attention for developing tunable and compact optical devices with excellent performances. In this paper, the dynamic manipulation of electromagnetically induced transparency (EIT) with high quality factors (Q-factors) is realized in the optical telecommunication range via the graphene-loaded all-dielectric metasurface. The all-dielectric metasurface is composed of split Si nanocuboids, and high Q-factor EIT resonance stems from the destructive interference between the toroidal dipole resonance and the magnetic dipole resonance. As graphene is integrated on the all-dielectric metasurface, the modulation of the EIT window is realized by tuning the Fermi level of graphene, engendering an appreciable modulation depth of 88%. Moreover, the group velocity can be tuned from c/1120 to c/3390. Our proposed metasurface has the potential for optical filters, modulators, and switches.
Highlights
Induced transparency (EIT) originates from a quantum interference in atomic physics, leading to the formation of a narrow transparency window within a broad absorption spectrum [1]
The Electromagnetically induced transparency (EIT) effect in metamaterials mainly results from two interference pathways: bright–dark mode coupling and bright–bright mode coupling [2,3]
Some schemes have been proposed to realize a dynamical control of the EIT effect based on metamaterials, such as liquid crystals [7], photoactive semiconductors [8], phase change media [9], and electrical control [10]
Summary
Induced transparency (EIT) originates from a quantum interference in atomic physics, leading to the formation of a narrow transparency window within a broad absorption spectrum [1] This concept was later extended to metamaterial systems. Hybrid graphene–dielectric metasurfaces exhibit excellent modulation performance based on Fano resonance [21,22,23] They are not suitable for optical switching. Combined with the advantages of graphene, it will be possible to actively control the high Q-factor EIT based on the toroidal dipole in all-dielectric metasurfaces. With the integration of graphene, the excellent performance of an optical switch is realized in the EIT window by tuning the Fermi level of graphene, accompanied by the active control of the slow-light effect
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
