In this paper, we demonstrate the combination of a dielectric metasurface with a graphene layer to realize a high performance toroidal resonance based optical modulator. The dielectric metasurface consists of two mirrored asymmetric silicon split-ring resonators (ASSRRs) that can support strong toroidal dipolar resonance with narrow line width (~0.77 nm) and high quality (Q)-factor (~1702) and contrast ratio (~100%). Numerical simulation results show that the transmission amplitude of the toroidal dipolar resonance can be efficiently modulated by varying the Fermi energy EF when the graphene layer is integrated with the dielectric metasurface, and a max transmission coefficient difference up to 78% is achieved indicating that the proposed hybrid graphene/dielectric metasurface shows good performance as an optical modulator. The effects of the asymmetry degree of the ASSRRs on the toroidal dipolar resonance are studied and the efficiency of the transmission amplitude modulation of graphene is also investigated. Our results may also provide potential applications in optical filter and bio-chemical sensing.
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http://dx.doi.org/10.1364/OE.25.026045 | DOI Listing |
Phys Rev Lett
December 2024
East China Normal University, State Key Laboratory of Precision Spectroscopy, and Hainan Institute, Shanghai, China.
We reveal a new scenario for the transition of solitons to chaos in a mode-locked fiber laser: the modulated subharmonic route. Its universality is confirmed in two different laser configurations, namely, a figure-of-eight and a ring laser. Numerical simulations of the laser models agree well with the experiments.
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Clermont INP, Institut Pascal, PHOTON-N2, Université Clermont Auvergne, CNRS, F-63000 Clermont-Ferrand, France.
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January 2025
College of Animal Science, Anhui Science and Technology University, Chuzhou, China.
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January 2025
Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K.
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Inherited retinal diseases (IRDs) are clinically and genetically heterogeneous disorders characterized by progressive photoreceptor degeneration and irreversible vision loss. MicroRNAs (miRNAs), a class of endogenous non-coding RNAs with post-transcriptional regulatory properties, are known to play a major role in retinal function, both in physiological and pathological conditions. Given their ability to simultaneously modulate multiple molecular pathways, miRNAs represent promising therapeutic tools for disorders with high genetic heterogeneity, such as IRDs.
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