- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Information Encoding with Optical Dielectric Metasurface via Independent Multichannels
摘要： Information encryption and security is a prerequisite for information technology which can be realized by optical metasurface owing to its arbitrary manipulation over the wavelength, polarization, phase and amplitude of light. So far information encoding can be implemented by the metasurface in one-dimensional (1D) mode (either wavelength or polarization) only with several combinations of independent channels. Herein, we design dielectric metasurfaces by multiplexing for information encoding in a two-dimensional (2D) mode of both wavelength and polarization. 63 combinations made out of six independent channels by two circular polarization states (RCP and LCP) and three visible wavelengths (633 nm, 532 nm and 473 nm) are experimentally demonstrated, in sharp contrast with 7 combinations by 3 independent channels in 1D mode. This 2D mode encoding strategy enhances the encryption security dramatically and paves a novel pathway for escalating the security level of information in multichannel information encryption, anti-counterfeiting, optical data storage, and information processing.
关键词： Pancharatnam-Berry phase,photon spin-dependent state,multichannel,information processing,multiwavelength,dielectric metasurface
更新于2025-09-04 15:30:14
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Range- and Aperture-dependent Motion Compensation based on Precise Frequency Division and Chirp Scaling for Synthetic Aperture Radar
摘要： The complicated vibrations of the radar sensor, referred to as motion error, generally produce extra range cell migration (RCM) along range direction as well as spectral replicas along azimuth direction, which severely impairs the quality of a focused synthetic aperture radar (SAR) image. This paper concerns the compensation of motion error which is deemed to be range- and aperture-dependent. To this end two pairs of relations: shift-range and angle-frequency, are analyzed. Based on the derived relations, we propose a chirp scaling based range envelope correction (CS-REC) to cope with the range-dependent position shifts (i.e., RCM) and a precise frequency division (PFD) approach to account for the residual aperture-dependent motion error. The proposed algorithm can compensate bulk and complicated motion error completely before range cell migration correction and ensure the focusing-quality of a SAR image without autofocus. Both simulated and real data experiments validate the effectiveness of the proposed algorithm.
关键词： chirp scaling,synthetic aperture radar,Range- and aperture-dependent motion compensation,precise frequency division
更新于2025-09-04 15:30:14
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Counteranion-Triggered and Excitation-Dependent Chemopalette Effect in a Supramolecular Dual-Emissive System Based on Cu <sub/>3</sub> Pz <sub/>3</sub>
摘要： Three Cu3Pz3-based isostructural complexes (Cu3L3)2(CuX)2 (labeled as 1-ClO4, 1-NO3, and 1-Br, where X = ClO4?, NO3?, and Br?, respectively) were prepared by solvothermal reactions of an angular bifunctional pyridyl?pyrazole ligand, 4-(pyridin-4′-ylthio)-3,5-dimethyl-1H-pyrazole (HL), with Cu(ClO4)2, Cu(NO3)2, and CuBr, respectively. Pyrazolate (Pz) groups are highly specific to form planar trinuclear Cu3Pz3 units. Two Cu3L3 units are further connected by two CuX units through NPy?Cu?NPy (Py = 4-pyridyl) bonds to form an octanuclear chairlike molecule (Cu3L3)2(CuX)2, which then self-assembles through intertrimeric cuprophilicity to construct chainlike supraaggregates featuring two luminophores, [Cu3Pz3]2 and CuPy2X. With different counteranions (ClO4?, NO3?, and Br?), the complexes give off various emissions from red to green upon UV irradiation. 1-ClO4 and 1-NO3 show only low-energy (LE) orange (λemmax = 585 nm) and red (λemmax = 640 nm) emissions, while 1-Br exhibits excitation-dependent (260?360 nm) emissions from yellow to green due to variation in the relative intensities of two resolvable emissions, high energy (HE, λemmax = 520 nm) and LE (λemmax = 630 nm). The dual emissions are assigned to 3CC (LE states) based on excimeric [Cu3Pz3]2 units and 3XLCT/3MLCT (HE states) based on CuPy2X units. This work realizes a chemopalette effect through regulations of the counteranion and excitation energy in a dual-emissive system. It provides valuable insights into the nature of dual-emissive materials and the further investigation of the photophysical mechanism in such a system.
关键词： Cu3Pz3-based complexes,excitation-dependent,dual-emissive system,counteranion-triggered,chemopalette effect
更新于2025-09-04 15:30:14