An Ultra-Narrowband Graphene-Perfect Absorber Based on Bound States in the Continuum of All-Dielectric Metasurfaces
Year: 2025
Type: article
Abstract: Enhancing light absorption in two-dimensional (2D) materials, particularly few-layer structures, is critical for advancing optoelectronic devices such as light sources, photodetectors, and sensors. However, conventional absorption enhancement strategies often suffer from unstable resonant wavelengths and low-quality factors (Q-factors) due to the inherent weak light-matter interactions in 2D materials. To address these limitations, we propose an all-dielectric metasurface graphene-perfect absorber based on toroidal dipole bound state in the continuum (TD-BIC) with an ultra-narrow bandwidth and stable resonant wavelength. The proposed structure achieves tunable absorption linewidths spanning three orders of magnitude (6 nm to 0.0076 nm) through critical coupling modulation. Furthermore, the operational wavelength can be flexibly extended to any near-infrared region by adjusting the grating width. This work establishes a novel paradigm for enhancing the absorption of 2D materials in photonic device applications.
Source: Nanomaterials
DOI: 10.3390/nano15141124
Authors: Qi Zhang, Xiao Zhang, Zhihong Zhu, Chucai Guo
Institution: National University of Defense Technology
Language: English
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,896
OpenAlex ID: W4412512606