Publications by authors named "Dezhi Tan"

Article Synopsis
  • Metal halide perovskites (MHPs) show promise but suffer from structural instability, particularly in high humidity, which limits their practical use.
  • Researchers discovered a method to grow nanowires (NWs) of MHP on glass surfaces under 85% humidity, allowing for tunable lengths and compositions.
  • These nanowire lasers demonstrated impressive qualities such as high quality factor and stability, opening up new possibilities for advanced optical applications.
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All-optical nonlinear activation functions (NAFs) are crucial for enabling rapid optical neural networks (ONNs). As linear matrix computation advances in integrated ONNs, on-chip all-optical NAFs face challenges such as limited integration, high latency, substantial power consumption, and a high activation threshold. In this work, we develop an integrated nonlinear optical activator based on the butt-coupling integration of two-dimensional (2D) MoTe and optical waveguides (OWGs).

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The direct laser writing (DLW) of photoluminescent metal clusters is inspiring intensive research in functional glasses. However, understanding the influence of the host structure on cluster formation and visualizing DLW-induced clusters at the atomic scale remains challenging. In this work, we develop a highly photosensitive fluorophosphate glass through fluorine incorporation.

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Three-dimensional (3D) glass chips are promising waveguide platforms for building hybrid 3D photonic circuits due to their 3D topological capabilities, large transparent windows, and low coupling dispersion. At present, the key challenge in scaling down a benchtop optical system to a glass chip is the lack of precise methods for controlling the mode field and optical coupling of 3D waveguide circuits. Here, we propose an overlap-controlled multi-scan (OCMS) method based on laser-direct lithography that allows customizing the refractive index profile of 3D waveguides with high spatial precision in a variety of glasses.

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Metal halide perovskite (MHP) structures that exhibit polarized photoluminescence (PL) have attracted significant interest in fabricating light field regulation elements for display, imaging, and information storage applications. We report a three-dimensional direct lithography of heterostructures for controllable polarized PL inside glass by laser-induced localized temperature engineering. The heterostructures consisted of oriented periodic structures (OPSs) and MHP nanocrystals, and the mechanism for hierarchical distribution of heterostructures was illustrated.

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Wavelength conversion based on hybrid inorganic-organic sensitized triplet-triplet annihilation upconversion (TTA-UC) is promising for applications such as photovoltaics, light-emitting-diodes, photocatalysis, additive manufacturing, and bioimaging. The efficiency of TTA-UC depends on the population of triplet excitons involved in triplet energy transfer (TET), the driving force in TET, and the coupling strength between the donor and acceptor. Consequently, achieving highly efficient TTA-UC necessitates the precise control of the electronic states of inorganic donors.

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Advanced coloration methods are of pivotal importance in science, technology, and engineering. However, 3D structural colors that are critical for emerging multidimensional information representation and recording are rarely achievable. Here, a facile voxel-level programmable 3D structural coloration in the bulk lithium niobate (LiNbO ) crystal is reported.

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Metal coordination compound (MCC) glasses [e.g., metal-organic framework (MOF) glass, coordination polymer glass, and metal inorganic-organic complex (MIOC) glass] are emerging members of the hybrid glass family.

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We report writing low-loss waveguides (WGs) by using a femtosecond laser in silica glass. A record low propagation loss of 0.07 dB/cm is achieved, and the lowest bend loss reaches 0.

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Material composition engineering and device fabrication of perovskite nanocrystals (PNCs) in solution can introduce organic contamination and entail several synthetic, processing, and stabilization steps. We report three-dimensional (3D) direct lithography of PNCs with tunable composition and bandgap in glass. The halide ion distribution was controlled at the nanoscale with ultrafast laser-induced liquid nanophase separation.

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Article Synopsis
  • The hinge structure in antimicrobial peptides enhances their flexibility, potentially boosting their ability to disrupt bacterial membranes and bind to intracellular targets, leading to increased antibacterial activity.
  • This structure also reduces rigidity, which may decrease cytotoxic effects on eukaryotic cells, making these peptides safer for use in therapeutic applications.
  • The article reviews the characteristics and impacts of the hinge structure and discusses its implications for the design and development of new antimicrobial peptides.
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This Letter describes the realization of long-term optical information storage in glass using an enhanced signal-to-noise ratio (SNR). We show that the photo-oxidation of ions in the glass matrix induced by ultraviolet light suppresses background signals, thereby enhancing by tenfold the SNR of ions photoluminescence (PL) of the dots written by a femtosecond (fs) laser. Thus, smaller dots exhibiting weak PL emission can be detected.

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Realizing general processing applicable to various materials by one basic tool has long been considered a distant dream. Fortunately, ultrafast laser-matter interaction has emerged as a highly universal platform with unprecedented optical phenomena and provided implementation paths for advanced manufacturing with novel functionalities. Here, we report the establishment of a three-dimensional (3D) focal-area interference field actively induced by a single ultrafast laser in transparent dielectrics.

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Femtosecond laser-induced modification in the glass has drawn considerable interest due to its widespread superiority in the applications of three-dimensional optical storage. In this Letter, we report that a single pulse could be used in optical memory with super-high writing speed. The photoluminescence image and spectrum indicate that one pulse-induced permanent photoreduction of to in -doped sodium aluminoborate glass can be achieved.

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We propose a strategy of temperature gradient assisted femtosecond laser writing for elaboration of low loss waveguides (WGs) over a large depth in glass. The matter flow driven by the temperature distribution is responsible for forming a highly densified WG core with tunable size. Importantly, the unique position of the guiding core outside the focus allows for abating the influence of laser energy redistribution and inscribing low loss deep WGs.

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Article Synopsis
  • Researchers created a heterojunction (HJ) using two 2D materials, GeSe and MoS, to explore their combined electrical and photoresponsive properties.
  • The study revealed significant rectification with high contrast in vertical tunneling, highlighting the efficiency of charge transport in the HJ.
  • The HJ demonstrated strong photoresponse, suggesting potential applications in electronics and optoelectronics due to its multifunctional capabilities.
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Layered materials, such as graphene, transition metal dichalcogenides and black phosphorene, have been established rapidly as intriguing building blocks for optoelectronic devices. Here, we introduce highly polarization sensitive, broadband, and high-temperature-operation photodetectors based on multilayer germanium sulfide (GeS). The GeS photodetector shows a high photoresponsivity of about 6.

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We report enhanced green and red upconversion (UC) luminescence in Ho3+-doped oxyfluoride germanate glass by introducing bismuth near-infrared active centers as sensitizers. The UC excitation bands at 750 and 970 nm show a full width at half-maximum of 20 and 45 nm, respectively. Energy transfer from sensitizers, the excited-state absorption, and phonon-coupled absorption of Ho3+ jointly contribute to the enhanced UC luminescence.

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We report that non-contact self-referencing temperature sensors can be realized with the use of core-shell nanostructures. These lanthanide-based nanothermometers (NaGdF4:Yb(3+)/Tm(3+)@Tb(3+)/Eu(3+)) exhibit higher sensitivity in a wide range from 125 to 300 K based on two emissions of Tb(3+) at 545 nm and Eu(3+) at 615 nm under near-infrared laser excitation.

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The effect of heat-treatment on the near-infrared (NIR) luminescence properties was studied in Bi-doped borate glasses. The luminescence intensity generally decreases with the increase of temperature, and the thermal stability can be improved by nearly 4.5 times with addition of 5 mol% La2O3.

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Carbon nanoparticles (CNPs), hollow CNPs, nanodiamonds, and hybrid graphene spheres (HGSPs) are produced by using fs laser ablation in solution. These carbon nanostructures emit tunable photoluminescence and two-photon luminescence. The photoinduced layer-by-layer assembly of graphene nanosheets is observed to form HGSPs with tailored broadly-ranged sizes for the first time.

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Nano/micro fibers doped with metal nanocrystals are of great interest both theorectically and practically. Nevertheless, the ordered assembly of metal nanocrystals with desired patterns in nano/micro fibers still remains a big challenge, which constrains the further development of the performance of the material. In this investigation, we propose a facile strategy based on the sol-gel and coaxial electrospinning technique to fabricate silica submicron fibers incorporating ordered 1D array of silver nanoparticles.

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Broadband near-infrared luminescence covering 900 to 1600 nm has been observed in Bi-doped oxyfluoride silicate glasses. The partial substitution of fluoride for oxide in Bi-doped silicate glasses leads to an increase of the intensity and lifetime of the near-infrared luminescence and blue-shift of the near-infrared emission peaks. Both Bi-doped silicate and oxyfluoride silicate glasses show visible luminescence with blue, green, orange and red emission bands when excited by ultra-violet light.

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A recent paper in this journal reported the synthesis of highly fluorescent crystalline carbon nanoparticles by microwave irradiation of sucrose with phosphoric acid. The emission wavelengths reported in this investigation are always twice the corresponding excitation wavelengths and the full widths at half maximum are extremely small (15-20 nm). We suggest that their results and discussions are questionable.

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