We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Lithography‐Free and High‐Generation Fractal Plasmonic Nanoantenna for Multispectral Infrared Sensing
Summary
Researchers developed a lithography-free gold fractal nanoantenna platform fabricated via film dewetting that supports multiple plasmonic resonances spanning from near-infrared to mid-infrared wavelengths for multispectral sensing applications. The fractal order could be controlled by adjusting dewetting times, overcoming the diffraction limit that constrains conventional lithography-based fabrication of higher-order fractals for enhanced infrared spectroscopy.
Abstract Fractal plasmonic nanoantennas are widely used in plasmon‐enhanced infrared spectroscopy and multiband sensing applications due to their inherent broadband and multispectral characteristics. However, conventional fractal antennas are typically fabricated by high‐cost, unscalable, and complicated lithography processes. The inevitable diffraction limit restricts the fabrication of higher‐order fractals and the improvement of multiband infrared response. In this study, a lithography‐free Au fractal nanoantenna platform is developed via film dewetting. The antennas can support multiple resonances over a broad spectral range spanning from near‐infrared to mid‐infrared. The fractal orders can be controlled by adjusting dewetting times. Moreover, due to the spontaneous fractal growth mechanism, the iteration number is theoretically unlimited. Through electromagnetic field simulation and infrared spectroscopy, the fractal order‐dependent multiband resonance mode and dense “hot spots” enabled electric‐field enhancement are revealed. Based on the infrared‐enhanced antenna, a minimum detection limit of 6 nm for the thickness of poly(methyl methacrylate) nanolayers is achieved. Additionally, a noninvasive sensor concept for glucose molecules in aqueous solution is demonstrated. This study presents a lithography‐free approach for constructing high‐generation and large‐area fractal nanoantennas with multiband resonance capabilities, which holds great promise for trace detection and high‐sensitivity biochemical sensing of various analytes in the near‐ to mid‐infrared spectral region.
Sign in to start a discussion.
More Papers Like This
Tuning the infrared resonance of thermal emission from metasurfaces working in near-infrared
Researchers designed and tested a metasurface — a precisely engineered array of tiny metal structures — that can control the wavelength of infrared light emitted or absorbed, demonstrating that adjusting the geometry and orientation of the structures allows fine-tuned control of the thermal emission spectrum for potential sensing and imaging applications.
Quasi‐Bound States in the Continuum Calibrated Broadband Metasurface Enhanced Mid‐Infrared Absorption Spectroscopy
Researchers developed a new infrared metasurface sensor design that uses quasi-bound states in the continuum as a built-in calibration reference for broadband molecular fingerprinting. The sensor enables trace-level detection and accurate spectral identification across a wide mid-infrared range. While focused on advancing sensing technology, this approach could have applications in detecting and identifying microplastic contaminants based on their chemical signatures.
In-situ Microplastic Detection Sensor based on Cascaded Microring Resonators
Researchers proposed an in-situ microplastic detection sensor using cascaded germanium-on-silicon microring resonators arranged to achieve the Vernier effect, enabling high-sensitivity analysis in near and mid-infrared spectral regions. The compact sensor design aims to replace bulky laboratory equipment for field detection of marine microplastics.
Broadband picometer-scale resolution on-chip spectrometer with reconfigurable photonics
Researchers demonstrated a miniaturized on-chip spectrometer that achieves both extremely fine spectral resolution (down to picometer scale) and broad operating bandwidth by using reconfigurable photonic circuits. The device uses a network of tunable optical filters to generate diverse spectral sampling patterns from a single chip. The study suggests this technology could enable portable, high-performance spectral analysis for applications ranging from environmental sensing to biomedical diagnostics.
Integrated reconstructive spectrometer with programmable photonic circuits
Researchers built a miniaturized on-chip light spectrometer using programmable photonic circuits that achieves high resolution across a wide range of wavelengths, outperforming existing compact spectrometers by roughly ten times — a breakthrough that could enable handheld devices for environmental or medical sensing applications.