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Optical waveguiding phenomena found in bioinspired chemically synthesized peptide nanostructures are a new paradigm which can revolutionize emerging fields of precise medicine and health monitoring. A unique combination of their intrinsic biocompatibility with remarkable multifunctional optical properties and developed nanotechnology of large peptide wafers makes them highly promising for new biomedical light therapy tools and implantable optical biochips. This Review highlights a new field of peptide nanophotonics. It covers peptide nanotechnology and the fabrication process of peptide integrated optical circuits, basic studies of linear and nonlinear optical phenomena in biological and bioinspired nanostructures, and their passive and active optical waveguiding. It is shown that the optical properties of this generation of bio‐optical materials are governed by fundamental biological processes. Refolding the peptide secondary structure is followed by wideband optical absorption and visible tunable fluorescence. In peptide optical waveguides, such a bio‐optical effect leads to switching from passive waveguiding mode in native α‐helical phase to an active one in the β‐sheet phase. The found active waveguiding effect in β‐sheet fiber structures below optical diffraction limit opens an avenue for the future development of new bionanophotonics in ultrathin peptide/protein fibrillar structures toward advanced biomedical nanotechnology. 相似文献
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Traditional cooling systems have been posing a significant challenge to the global energy crisis and climate change due to the high energy consumption of the cooling process. In recent years, the emerging daytime radiative cooling provides a promising solution to address the bottleneck of traditional cooling technology by passively dissipating heat radiation to outer space without any energy consumption through the atmospheric transparency window(8~13μm). Whereas its stringent optical criteria require sophisticated and high cost fabrication producers, which hinders the applicability of radiative cooling technology. Many efforts have been devoted to develop high-efficiency and low-cost daytime radiative cooling technologies for practical application, including the nanophotonics based artificial strategy and bioinspired strategy. In order to systematically summarize the development and latest advance of daytime radiative cooling to help developing the most promising approach, here in this paper we will review and compare the two typical strategies on exploring the prospect approach for applicable radiative cooling technology. We will firstly sketch the fundamental of radiative cooling and summarize the common methods for construction radiative cooling devices. Then we will put an emphasis on the summarization and comparison of the two strategies for designing the radiative cooling device, and outlook the prospect and extending application of the daytime radiative cooling technology. 相似文献
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C. Favazza J. Trice A. K. Gangopadhyay H. Garcia R. Sureshkumar Ramki Kalyanaraman 《Journal of Electronic Materials》2006,35(8):1618-1620
Most metals on SiO2 have a finite contact angle and are therefore subject to dewetting during thermal processing. The resulting dewetting morphology
is determined primarily by nucleation and growth or instabilities. The dewetting mechanism implies a disordered spatial arrangement
for homogeneous nucleation, but an ordered one for instabilities such as spinodal decomposition. Here, we show that the morphology
of laser-melted ultrathin Co film (4-nm thick) can be attributed to dewetting via an instability. Dewetting leads to breakup
of the continuous Co film into nanoparticles with a monomodal size distribution with an average particle diameter of 75 nm±23
nm. These nanoparticles have short-range order (SRO) of 130 nm in their separation. This result has important implications
for nanomanufacturing with a robust spacing or size selection of nanoparticles in addition to spatial ordering. 相似文献
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Vishal Jain ;Ali Nowzari ;Jesper Wallentin ;Magnus T. Borgstrom ;Maria E. Messing ;Damir Asoli ;Mariusz Graczyk ;Bemd Witzigmann ;Federico Capasso ;Lars Samuelson ;Hakan Pettersson 《Nano Research》2014,(4):544-552
We report on electrical and optical properties of p+-i-n+ photodetectors/solar cells based on square millimeter arrays of InP nanowires (NWs) grown on InP substrates. The study includes a sample series where the p+-segment length was varied between 0 and 250 nm, as well as solar cells with 9.3% efficiency with similar design. The electrical data for all devices display clear rectifying behavior with an ideality factor between 1.8 and 2.5 at 300 K. From spectrally resolved photocurrent measurements, we conclude that the photocurrent generation process depends strongly on the p~-segment length. Without a p+-segment, photogenerated carriers funneled from the substrate into the NWs contribute strongly to the photocurrent. Adding a p+-segment decouples the substrate and shifts the depletion region, and collection of photogenerated carriers, to the NWs, in agreement with theoretical modeling. In optimized solar cells, clear spectral signatures of interband transitions in the zinc blende and wurtzite InP layers of the mixed-phase i-segments are observed. Complementary electroluminescence, transmission electron microscopy (TEM), as well as measurements of the dependence of the photocurrent on angle of incidence and polarization, support our interpretations. 相似文献
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Matthew Delaney Ioannis Zeimpekis Daniel Lawson Daniel W. Hewak Otto L. Muskens 《Advanced functional materials》2020,30(36)
Phase‐change materials (PCMs) are seeing tremendous interest for their use in reconfigurable photonic devices; however, the most common PCMs exhibit a large absorption loss in one or both states. Here, Sb2S3 and Sb2Se3 are demonstrated as a class of low loss, reversible alternatives to the standard commercially available chalcogenide PCMs. A contrast of refractive index of Δn = 0.60 for Sb2S3 and Δn = 0.77 for Sb2Se3 is reported, while maintaining very low losses (k < 10?5) in the telecommunications C‐band at 1550 nm. With a stronger absorption in the visible spectrum, Sb2Se3 allows for reversible optical switching using conventional visible wavelength lasers. Here, a stable switching endurance of better than 4000 cycles is demonstrated. To deal with the essentially zero intrinsic absorption losses, a new figure of merit (FOM) is introduced taking into account the measured waveguide losses when integrating these materials onto a standard silicon photonics platform. The FOM of 29 rad phase shift per dB of loss for Sb2Se3 outperforms Ge2Sb2Te5 by two orders of magnitude and paves the way for on‐chip programmable phase control. These truly low‐loss switchable materials open up new directions in programmable integrated photonic circuits, switchable metasurfaces, and nanophotonic devices. 相似文献
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Covert Photonic Barcodes Based on Light Controlled Acidichromism in Organic Dye Doped Whispering‐Gallery‐Mode Microdisks 下载免费PDF全文
Zhenhua Gao Cong Wei Yongli Yan Wei Zhang Haiyun Dong Jinyang Zhao Jun Yi Chunhuan Zhang Yong Jun Li Yong Sheng Zhao 《Advanced materials (Deerfield Beach, Fla.)》2017,29(30)
Photonic barcodes with a small footprint have demonstrated a great value for multiplexed high‐throughput bioassays and tracking systems. Attempts to develop coding technology tend to focus on the generation of featured barcodes both with high coding capacity and accurate recognition. In this work, a strategy to design photonic barcodes is proposed based on whispering‐gallery‐mode (WGM) modulations in dye‐doped microdisk resonant cavities, where each modulated photoluminescence spectrum constitutes the fingerprint of a corresponding microdisk. The WGM‐based barcodes can achieve infinite encoding capacity through tuning the dimensions of the microdisks. These photonic barcodes can be well disguised and decoded based on the light controlled proton release and acidichromism of the organic materials, which are essential to fulfill the functions of anti‐counterfeiting, information security, and so on. The results will pave an avenue to new types of flexible WGM‐based components for optical data recording and security labels. 相似文献
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Davide Piccinotti Behrad Gholipour Jin Yao Kevin F. MacDonald Brian E. Hayden Nikolay I. Zheludev 《Advanced materials (Deerfield Beach, Fla.)》2019,31(14)
A variety of alternative plasmonic and dielectric material platforms—among them nitrides, semiconductors, and conductive oxides—have come to prominence in recent years as means to address the shortcomings of noble metals (including Joule losses, cost, and passive character) in certain nanophotonic and optical‐frequency metamaterial applications. Here, it is shown that chalcogenide semiconductor alloys offer a uniquely broad pallet of optical properties, complementary to those of existing material platforms, which can be controlled by stoichiometric design. Using combinatorial high‐throughput techniques, the extraordinary epsilon‐near‐zero, plasmonic, and low/high‐index characteristics of Bi:Sb:Te alloys are explored. Depending upon composition they can, for example, have plasmonic figures of merit higher than conductive oxides and nitrides across the entire UV–NIR range, and higher than gold below 550 nm; present dielectric figures of merit better than conductive oxides at near‐infrared telecommunications wavelengths; and exhibit record‐breaking refractive indices as low as 0.7 and as high as 11.5. 相似文献