Bessel beam arrays are progressively attracting attention in recent years due to their remarkable non‐diffracting nature and parallel manipulation capabilities in diverse applications. However, the poor phase discretization of conventional approaches such as spatial light modulators leads to low numerical aperture (NA) beam arrays due to the limitation imposed by the Nyquist sampling theorem and poor uniformity of the beam intensity. The key contribution of this study is to experimentally demonstrate the generation of high‐uniformity and high‐resolution Bessel beam arrays by utilizing all‐dielectric metasurfaces. This is attained by optimizing the design of the supercell of a Dammann grating, particularly decreasing each supercell of the grating to a proper size. We demonstrate a 4 × 4 array of Bessel beams with a subwavelength transverse dimension (570 nm, ∼0.9 λ ) and a large NA of 0.4 for each beam in the array, while maintaining a relatively high uniformity intensity (52.40%) for the array. Additionally, the Bessel beam arrays are generated in a broadband range through the proposed all‐dielectric metasurfaces. Our results are of great significance and particularly useful for applications of metasurface‐based Bessel beam arrays in multidisciplinary fields such as laser fabrication, biomedical imaging, data storage, and multi‐particle trapping.

Concentration gradient generation and mixed combinations of multiple solutions are of great value in the field of biomedical research.

Fluorescent carbon dots (CDs) are a new type of photoluminescent nanomaterial. Solid-state CDs usually undergo fluorescence quenching due to direct π-π* interactions and superabundant energy resonance transfer. Therefore, the preparation of solid-state fluorescent CDs is a challenge, especially the preparation of long wavelength solid-state CDs. In this research, long wavelength emission CDs were successfully synthesized by solvothermal methods, and the prepared CDs showed good hydrophobicity. The composite solid-state CDs/PVP (Polyvinyl pyrrolidone) can emit strong red fluorescence, and the quantum yield (QY) of the CDs/PVP powder reaches 18.9%. The prepared CDs/PVP solid-state powder was successfully applied to latent fingerprint detection. The results indicate that the latent fingerprints developed by CDs/PVP powder have a fine definition and high contrast visualization effect, which proves that the prepared CDs/PVP has great application potential in latent fingerprint detection. This study may provide inspiration and ideas for the design of new hydrophobic CDs.

A series of TiN/ITO composite films with various thickness of ITO buffer layer were fabricated in this study. The enhancement of optical properties was realized in the composite thin films. The absorption spectra showed that absorption intensity in the near-infrared region was obviously enhanced with the increase of ITO thickness due to the coupling of surface plasma between TiN and ITO. The epsilon-near-zero wavelength of this composite can be tuned from 935 nm to 1895 nm by varying the thickness of ITO thin films. The nonlinear optical property investigated by Z-scan technique showed that the nonlinear absorption coefficient (β = 3.03 × 10⁻⁴ cm/W) for the composite was about 14.02 times greater than that of single-layer TiN films. The theoretical calculations performed by finite difference time domain were in good agreement with those of the experiments.

In this paper, La₂Ce₂O₇ powders co-activated by Ho³⁺ and Yb³⁺ were synthesized by a high temperature solid-state reaction. Both Ho³⁺ and Yb³⁺ substitute the La³⁺ sites in the La₂Ce₂O₇ lattice, where the Ho³⁺ concentration is 0.5 at.% and the Yb³⁺ concentration varies in the range of 10~18% at.%. Pumped by a 980 nm laser, the up-conversion (UC) green emission peak at 547 nm and the red emission at 661 nm were detected. When the doping concentration of Ho³⁺ and Yb³⁺ are 0.5 at.% and 14% at.%, respectively, the UC emission reaches the strongest intensity. The temperature-sensing performance of La₂Ce₂O₇:Ho³⁺ with Yb³⁺ was studied in the temperature range of 303–483 K, where the highest relative sensitivity (S_r) is 0.0129 K⁻¹ at 483 K. The results show that the powder La₂Ce₂O₇:Ho³⁺, Yb³⁺ can be a potential candidate for remote temperature sensors.

Capillary electrophoresis (CE) is a versatile analytical separation method in the field of biochemistry. Although it has been proved that the relative molecular mass (M_r) of the polymers determines the threshold concentration of the entangled polymer solution, which will affect the separation performance of DNA molecules, there is still no report on the effect of M_r on the separation performance of proteins. Herein, we have thoroughly performed the CE of proteins ranged from 14.3 kDa to 116 kDa in a mixed hydroxyethyl cellulose (HEC) solution. The mixed solution was obtained with various M_r including 90,000, 250,000, 720,000, and 1,300,000. Then, we found that the mixed polymer provided a high resolution for small protein molecules while increasing the efficiency of large ones. Results demonstrated that the migration time decreased if HEC (1,300,000) was mixed with the lower M_r one, and the mixed solution (1,300,000/250,000) offered the highest resolution. The resolution was negatively correlated with the electric field strength. Finally, we have employed the optimal electrophoretic conditions to separate proteins in human tears, and it showed that lysozyme, lipocalin, and lactoferrin from human tears were successfully resolved in the mixed HEC. Such work indicates that CE has the potential to be developed as a tool for the diagnosis of xerophthalmia, meibomian gland dysfunction, or other eye diseases.