We imprint plasmonic near field enhancements as nanoscale topography in SU8 photoresist using two-photon absorption from a spectrally filtered broadband supercontinuum light source. Imprinted patterns smaller than 50 nm across are obtained localized at positions of high local field enhancements in gold bow tie antennas, and gold split rings resonant in the visible and near-infrared. Enhanced exposure only occurs at wavelengths and polarizations that exactly match the plasmonic resonances. Hence our work demonstrates that wavelength selective addressing of hot spots for nanolithography using an inexpensive, low peak-power picosecond pulsed source is freely tunable throughout the visible and infrared to match any desired plasmon resonance.
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http://dx.doi.org/10.1364/OE.19.011405 | DOI Listing |
Materials (Basel)
December 2024
Department of Chemical and Materials Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 807, Taiwan.
This study employed a hydrothermal method to coat CuS onto PbS quantum dots loaded with ZnO, resulting in a core-shell-structured (PbS/ZnO)@CuS hetero-structured photocatalyst. The sulfide coating enhanced the photocatalyst's absorption in the near-infrared to visible light range and effectively reduced electron-hole (h) pair recombination during photocatalytic processes. Electron microscopy analysis confirmed the successful synthesis of this core-shell structure using polyvinylpyrrolidone (PVP); however, the spatial hindrance effect of PVP led to a disordered arrangement of the CuS lattice, facilitating electron-hole recombination.
View Article and Find Full Text PDFNat Commun
January 2025
Interdisciplinary Science Center, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 100101, Beijing, China.
Fluorogenic RNA aptamers have various applications, including use as fluorescent tags for imaging RNA trafficking and as indicators of RNA-based sensors that exhibit fluorescence upon binding small-molecule fluorophores in living cells. Current fluorogenic RNA:fluorophore complexes typically emit visible fluorescence. However, it is challenging to develop fluorogenic RNA with near-infrared (NIR) fluorescence for in vivo imaging and sensing studies.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Osaka University Graduate School of Engineering Science School of Engineering Science: Osaka Daigaku Daigakuin Kiso Kogaku Kenkyuka Kiso Kogakubu, Department of Materials Engineering Science, Machikaneyama 1-3, 560-8531, Toyonaka, JAPAN.
An overcrowded ethylene composed of electron-donating anion, naphthoxide, and electron-accepting cation, acridinium, has been synthesized. It is in equilibrium between a folded conformer having a smaller permanent dipole moment with visible light absorption and a twisted conformer having a larger permanent dipole moment with NIR light absorption. The overcrowded ethylene shows multiple NIR chromisms, such as solvatochromism, thermochromism, mechanochromism, vapochromism, halochromism, and amphoteric electrochromisms, which are caused by the conformational change between folded and twisted conformers or by controlling the energy difference between the HOMO of the donor moiety and the LUMO of the acceptor moiety.
View Article and Find Full Text PDFJ Mater Chem B
January 2025
Department of Chemistry, University of North Dakota, Grand Forks, ND, 58202, USA.
Regulation of gene expression in eukaryotic cells is critical for cell survival, proliferation, and cell fate determination. Misregulation of gene expression can have substantial, negative consequences that result in disease or tissue dysfunction that can be targeted for therapeutic intervention. Several strategies to inhibit gene expression at the level of mRNA transcription and translation have been developed, such as anti-sense inhibition and CRISPR-Cas9 gene editing.
View Article and Find Full Text PDFPlant Biotechnol J
January 2025
School of Wine & Horticulture, Ningxia University, Yinchuan, Ningxia, China.
Superoxide dismutase (SOD) plays an important role to respond in the defence against damage when tomato leaves are under different types of adversity stresses. This work employed microhyperspectral imaging (MHSI) and visible near-infrared (Vis-NIR) hyperspectral imaging (HSI) technologies to predict tomato leaf SOD activity. The macroscopic model of SOD activity in tomato leaves was constructed using the convolutional neural network in conjunction with the long and short-term temporal memory (CNN-LSTM) technique.
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