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many irreplaceable advantages of high storage capacity, miniaturization, multi plicity, and integration capability. [6][7][8][9][10][11] Among various microoptics/nano optics devices, metasurface, consisting of planar subwavelength structures, has emerged as a particularly powerful plat form for modulating light parameters such as amplitude, [12,13] phase, [14][15][16] wavelength, [17][18][19][20] polarization, [4,[21][22][23] and hybrid parameters, [24,25] which provides the possibility of potential applications of information encryption, data storage, and optical communication. [26][27][28] Microprint and holography are often used as two separate optical encryption strategies applied in independent meta surface devices, which can be achieved by controlling over plasmonic [29][30][31][32][33][34] or all dielectric [35][36][37][38][39][40] structures at the nanoscale. To strengthen optical information secu rity, other parametric freedoms such as polarization, [41][42][43][44][45] wavelength, [17,[46][47][48][49] and spatial freedom [50][51][52] have been explored to achieve multiplexed microprint or holography encryption devices. Very recently, attempts have been imple mented to combine the microprint and holography in a single device. [53][54][55] However, although the combination of holography and microprints brings about the increase of encrypted dimen sions, crosstalk between different channels remains a thorny problem, and devices will not transmit repeatedly between senders and receivers once fabricated. Fabry-Pérot (FP) cavity resonators with narrow spectral linewidth can effectively sup press crosstalk and can be integrated to act as color filters, [56,57] which provides a potential solution. However, significant chal lenges such as realtime encryption, transmission security, and data compactness still need to be overcome.Here, we propose a novel type of metasurfacebased device that combines color FP cavitybased microprint and helicity multiplexed metahologram. Such devices have the encryption dimensions of microprint, holography as well as helicity at the same time by independently manipulating the amplitude, phase, and polarization of the incident light. A specific algo rithmic framework is developed to combine holography with structural color, and the particle swarm optimization (PSO) algorithm is built to optimize the conversion efficiencies of metasurface elements. Furthermore, enabled by a microprint of editable quick response (QR) code, a realtime encryption Optical encryption with multichannel, high complexity, and artistry characteristics has become one of the most significant approaches for modern information security. Recently emerged metasurface-based optics consisting of planar subwavelength metamaterials has been engineered as an ideal platform for optical encryption because of its capability of manipulating various optical parameters and enhancing information storage capacity. However, limited encrypted channels and insufficient real-time encryption abilities hinder its practical applicatio...

Porous ultrathin carbon nanobubbles formed carbon nanofiber webs exhibit 94.1% capacitance retention after 35 000 cycles at a current density of 10 A g−1.

This paper reports a hybrid nanoantenna consisting of an inner metal nanodisk and an outer dielectric ring cavity with superior fluorescence enhancement performance. Based on the multipole decomposition analysis and the coupled oscillator model, it is found that the surface plasmon resonance of the metal nanodisk could interact with the magnetic dipole mode of the dielectric ring more strongly than the electric dipole mode, improving the excitation rate in the gap region by more than 1 order of magnitude compared to those from the pure metal or dielectric constituent. The hybrid structure partially inherits the low loss advantage of the dielectric component, dramatically boosting the radiative decay rate and generating a decent quantum yield. The enhancement factor for a single emitter could reach more than one order of magnitude higher than those from the pure metal and dielectric counterparts, depending on the emitter's location and orientation. The overall emission intensity of multiple randomly oriented emitters are estimated via the reciprocity principle, which can reach more than 1500 than that in free space and nearly 2 orders of magnitude higher than those from pure metal or dielectric counterparts. On top of that, an excellent directional radiation pattern is obtained in the hybrid configuration with a maximum directivity enhancement >3000, and 74% of total power propagates upwardly. This robust hybrid structure shows the possibility to leverage the advantages from both metal and dielectric, which could be useful in fluorescence sensing, nonlinear optics, and quantum photonics.

Using panel data on 30 provinces in China from 2005 to 2012, this paper conducts an empirical test on the threshold effect of the relationship between financial development and carbon emission intensity from the perspectives of financial scale and financial efficiency. The results show that at a low level of per capita GDP, the expansion of the financial scale and the enhancement of financial efficiency will increase carbon intensity. When the per capita GDP is greater than the threshold value (RMB 37,410), the expansion of the financial scale will also increase carbon intensity, but the potency of this effect will be weaker. At the same time, the improvement of financial efficiency will help reduce carbon intensity. Most provinces with per capita GDP greater than the threshold value (RMB 37,410) are located in the eastern coastal areas of China, whereas most provinces with per capita GDP less than the threshold value are located in the central and western areas of China. Both raising the level of openness and improving the industrial structure will have significantly positive effects on carbon intensity.

Low-carbon pilot (LCP) policy aims to not only achieve economic development but also address climate change problems in China. With a difference-in-difference (DID) approach, this study provides empirical evidence to support the policy's implementation by analysing its impacts on green total factor productivity (GTFP). We find that the implementation of the low-carbon pilot policy has a significant positive impact on GTFP. The low-carbon pilot policy significantly improves the GTFP in the year following implementation, and its efficacy diminishes over time. In terms of mechanism analysis, the policy enables China to achieve win-win development through industry structure adjustment and foreign direct investment (FDI) inflows. Innovation does not immediately improve GTFP, although the low-carbon pilot policy promotes regional innovation. Our results provide strong support for China's recent third set of low-carbon pilot policies. As for global mitigation strategy, countries should incorporate the low-carbon development path into their strategic planning. In particular, developing countries should enforce more efforts on low-carbon development as such development path may improve their green productivity. It helps narrow the gap between developing and developed countries. Keywords Low carbon pilot policy . Win-win development . Green total factor productivity .

Reliable fabrication of gold nanoparticles with desirable size, geometry and spatial arrangement is essential for plasmonic applications.

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