Plasmonic and metamaterial based nano/micro-structured materials enable spectrally selective resonant absorption, where the resonant bandwidth and absorption intensity can be engineered by controlling the size and geometry of nanostructures. Here, we demonstrate a simple, lithography-free approach for obtaining a resonant and dynamically tunable broadband absorber based on vanadium dioxide (VO2) phase transition. Using planar layered thin film structures, where top layer is chosen to be an ultrathin (20 nm) VO2 film, we demonstrate broadband IR light absorption tuning (from ~90% to ~30% in measured absorption) over the entire mid-wavelength infrared spectrum. Our numerical and experimental results indicate that the bandwidth of the absorption bands can be controlled by changing the dielectric spacer layer thickness. Broadband tunable absorbers can find applications in absorption filters, thermal emitters, thermophotovoltaics and sensing.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4543955 | PMC |
http://dx.doi.org/10.1038/srep13384 | DOI Listing |
Sci Rep
January 2025
School of Electronic Science and Engineering, Xiamen University, Xiamen, 361005, China.
Vanadium dioxide (VO) exhibits exceptional phase transition characteristics that enable dynamic manipulation of electromagnetic wave. In this study, a novel design of bilayer isotropic metasurface is introduced. It leverages insulating-to-metallic phase transition of VO to enable broadband holography for terahertz wave.
View Article and Find Full Text PDFNat Commun
January 2025
State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, China.
The insulator-to-metal transition in VO has garnered extensive attention for its potential applications in ultrafast switches, neuronal network architectures, and storage technologies. However, the photoinduced insulator-to-metal transition remains controversial, especially whether a complete structural transformation from the monoclinic to rutile phase is necessary. Here we employ the real-time time-dependent density functional theory to track the dynamic evolution of atomic and electronic structures in photoexcited VO, revealing the emergence of a long-lived monoclinic metal phase under low electronic excitation.
View Article and Find Full Text PDFACS Nano
January 2025
Brno University of Technology, Central European Institute of Technology, Purkyňova 123, 612 00 Brno, Czech Republic.
Vanadium dioxide (VO) has received significant interest in the context of nanophotonic metamaterials and memories owing to its reversible insulator-metal transition associated with significant changes in its optical and electronic properties. The phase transition of VO has been extensively studied for several decades, and the ways how to control its hysteresis characteristics relevant for memory applications have significantly improved. However, the hysteresis dynamics and stability of coexisting phases during the transition have not been studied on the level of individual single-crystal VO nanoparticles (NPs), although they represent the fundamental component of ordinary polycrystalline films and can also act like nanoscale memory units on their own.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Anhui Province Key Laboratory for Control and Applications of Optoelectronic Information Materials, School of Physics and Electronic Information, Anhui Normal University, 189 Jiuhua South Road, Wuhu 241003, China.
Integrating metal nanoparticles with vanadium dioxide (VO) is an effective means to realize active plasmonic regulation which has great application potential in optical devices that respond in real-time to external stimuli. However, the high temperature necessary for VO growth severely reshapes the metal nanoparticles, causing reduced refractive index (RI) sensitivity and degraded modulation performance. Herein, we construct a large-area dynamically tunable plasmonic system composed of a VO-covered array of hexagonal gold nanoplates (AuNPLs).
View Article and Find Full Text PDFNanophotonics
November 2024
National Key Laboratory of Optical Field Manipulation Science and Technology, Chinese Academy of Sciences, Chengdu 610209, China.
Non-local metasurface supporting geometric phases at bound states in the continuum (BIC) simultaneously enables sharp spectral resonances and spatial wavefront shaping, thus providing a diversified optical platform for multifunctional devices. However, a static nonlocal metasurface cannot manipulate multiple degrees of freedom (DOFs), making it difficult to achieve multifunctional integration and be applied in different scenarios. Here, we presented and demonstrated phase-change non-local metasurfaces that can realize dynamic manipulation of multiple DOFs including resonant frequency, values, band, and spatial wavefront.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!