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Erbium-doped SnO2 films and devices are fabricated on silicon substrates, and the 1.54 μm emission of erbium ions is realized via energy transfer from the SnO2 host. It is found that the luminescence intensity for SnO2:Er film can be enhanced, by increasing the optical activity and transition probability of Er3+ ions with fluorine codoping. Moreover, the device prepared by the fluorine codoped SnO2 film presents a low turn-on voltage of 1.6 V and an onset electric field of 0.18 MV/cm. The unpackaged device operated for 1028h in the atmosphere, then continued to function at 40 °C/30% RH during 1003 h, with less than 10% optical power attenuation. Through further optimizing the preparation process, the optimal device exhibits an optical power density of 38.5 μW/cm2 at 1.55 μm, due to the improved crystalline quality together with the number of sensitizers. This work demonstrates the practical application potential in silicon-based light sources from erbium-doped SnO2 devices. [ABSTRACT FROM AUTHOR]

In this work, a hollow MoSe2/CuS type-II heterojunction was fabricated using hollow MoSe2 nanospheres as the basis for structural design. UV–Vis–NIR diffuse absorption tests show that MoSe2/CuS has a broad spectral absorption to extend the optical response range from UV–Vis to NIR. The light source utilization rate and interfacial area are increased by the hollow MoSe2/CuS core–shell structure. The broad absorption ability of MoSe2/CuS can facilitate the photocatalysis process. As the electrochemical impedance of MoSe2/CuS is lower than that of the MoSe2, MoSe2/CuS has a good photogenerated carrier separation efficiency. Benefiting from the synergistic facilitation effect of the multi-level 3D hollow nanosphere and the significant space charge region in type-II heterojunction, the RhB degradation efficiency of MoSe2/CuS reached 96.0% in 120.0 min under Xe (350 W) broadband spectrum light irradiation. The photocatalysis mechanism of the hollow MoSe2/CuS core–shell structure was investigated. This work provides an insight into the application of broad spectrum semiconductor heterojunctions to solve environmental problems. [ABSTRACT FROM AUTHOR]

When a diamagnetic graphite plate is placed on top of a magnet, it is subject to both magnetic levitation and gravitational forces. Computational modeling is used to demonstrate that these forces can balance each other to allow a stable tilt angle θ to be attained when the graphite plate pivots on the magnet surface. θ depends on the magnetic susceptibility χmag, which can be controlled by using laser irradiation to change the temperature of the graphite. Over a limited temperature range, there is a linear relation between the angle change Δθ and the temperature change ΔT. This predicted behavior is confirmed experimentally using a graphite plate (5 × 5 × 0.83 mm) placed on top of a 7.5 cm diameter neodymium iron boride magnet with a surface field strength of ∼5000 G. Using a 532 nm laser, θ could be continuously tuned from 52° to 26° by varying the laser power between 20 and 800 mW. The response time was about 15 s at all powers. Higher laser powers were observed to lead to a complete loss of levitation, followed by recovery and oscillation in and out of the laser beam. The linear dependence of Δθ on power suggests that photothermal tilting of the graphite plate in a magnetic field provides a fatigue resistant way to achieve large angular deviations using an external light source. This effect can be harnessed to function as a laser-controlled beam steering device. [ABSTRACT FROM AUTHOR]

Time-Resolved Serial Femtosecond Crystallography (TR-SFX) conducted at X-ray Free Electron Lasers (XFELs) has become a powerful tool for capturing macromolecular structural movies of light-initiated processes. As the capabilities of XFELs advance, we anticipate that a new range of coherent control and structural Raman measurements will become achievable. Shorter optical and x-ray pulse durations and increasingly more exotic pulse regimes are becoming available at free electron lasers. Moreover, with high repetition enabled by the superconducting technology of European XFEL (EuXFEL) and Linac Coherent Light Source (LCLS-II) , it will be possible to improve the signal-to-noise ratio of the light-induced differences, allowing for the observation of vibronic motion on the sub-Angstrom level. To predict and assign this coherent motion, which is measurable with a structural technique, new theoretical approaches must be developed. In this paper, we present a theoretical density matrix approach to model the various population and coherent dynamics of a system, which considers molecular system parameters and excitation conditions. We emphasize the use of the Wigner transform of the time-dependent density matrix, which provides a phase space representation that can be directly compared to the experimental positional displacements measured in a TR-SFX experiment. Here, we extend the results from simple models to include more realistic schemes that include large relaxation terms. We explore a variety of pulse schemes using multiple model systems using realistic parameters. An open-source software package is provided to perform the density matrix simulation and Wigner transformations. The open-source software allows us to define any arbitrary level schemes as well as any arbitrary electric field in the interaction Hamiltonian. [ABSTRACT FROM AUTHOR]

Advances in coherent light sources and development of pump–probe techniques in recent decades have opened the way to study electronic motion in its natural time scale. When an ultrashort laser pulse interacts with a molecular target, a coherent superposition of electronic states is created and the triggered electron dynamics is coupled to the nuclear motion. A natural and computationally efficient choice to simulate this correlated dynamics is a trajectory-based method where the quantum-mechanical electronic evolution is coupled to a classical-like nuclear dynamics. These methods must approximate the initial correlated electron–nuclear state by associating an initial electronic wavefunction to each classical trajectory in the ensemble. Different possibilities exist that reproduce the initial populations of the exact molecular wavefunction when represented in a basis. We show that different choices yield different dynamics and explore the effect of this choice in Ehrenfest, surface hopping, and exact-factorization-based coupled-trajectory schemes in a one-dimensional two-electronic-state model system that can be solved numerically exactly. This work aims to clarify the problems that standard trajectory-based techniques might have when a coherent superposition of electronic states is created to initialize the dynamics, to discuss what properties and observables are affected by different choices of electronic initial conditions and to point out the importance of quantum-momentum-induced electronic transitions in coupled-trajectory schemes. [ABSTRACT FROM AUTHOR]

Researching ultrafast dynamics and creating coherent light sources will both benefit significantly from the establishment of polarization control in high-order harmonic generation (HHG). By employing the time-dependent density functional theory method, we investigate HHG of carbonyl sulfide molecules using a combination of a linear polarized infrared (IR) laser and a weaker orthogonal Terahertz (THz) field. Our findings show that by adjusting the amplitude of the THz field, the movement scale of electrons in the THz direction can be tuned, thereby one can control the harmonic intensity in the IR laser direction. This method allows for the creation of near-circularly polarized attosecond pulses. Furthermore, the ellipticity of the attosecond pulse may be changed by modifying the carrier-envelope phase of the IR laser pulse. [ABSTRACT FROM AUTHOR]

Acquiring the thickness field of a soap film from interference colors requires an accurate relationship between color and film thickness. Throughout the literature, an interference relation derived using monochromatic waves is widely used to calculate the colors of soap films illuminated by light sources with significant frequency bandwidths by applying the relation at a number of discrete wavelengths in the source, which assumes that the interfering waves are perfectly coherent. However, since the coherence between waves is expected to decrease with increasing film thickness, it is poorly understood when interference relations derived using monochromatic waves can be applied. In this study, an interference relation incorporating the coherence between interfering waves is derived. The effects of coherence on the interference colors of soap films are then studied by comparing the colors computed using each of these two interference relations for light sources with different frequency bandwidths. As the frequency bandwidth of the light source increases, the difference in the colors computed using each interference relation increases, which implies that the accuracy of the method involving the monochromatic relation decreases with increasing frequency bandwidth of the source. The findings of this study will allow for more accurate measurements of the thickness of soap films from their interference colors. [ABSTRACT FROM AUTHOR]

Alpha-fetoprotein (AFP) is a characteristic marker of liver cancer, and its accurate detection is of great significance for the early detection of liver cancer. This study utilizes visible light as the excitation light source, employs electrochemical measurement, and incorporates the AFP aptamer as the biorecognition element to construct a photoelectrochemical (PEC) biosensor for the highly sensitive detection of AFP. A Z-scheme heterostructure is constructed via a two-step hydrothermal method, and CdS nanoparticles are anchored on TiO2NRA and BiOI nanosheets with high specific surface areas. The photocurrent response of the BiOI/CdS/TiO2NRA composite material is 4.5 times that of TiO2NRA. By analyzing the energy band positions, the electron transfer mechanisms of Z-scheme heterojunctions in CdS/TiO2NRA and BiOI/CdS photoactive materials were elucidated. Subsequently, the AFP aptamer was immobilized on the base electrode surface via the C＝N structure to fabricate a self-supporting sensing platform. The PEC biosensor demonstrates excellent detection performance within the linear range of 1 nM ∼ 250 nM, exhibiting high selectivity and the detection limit is 0.59 nM (S/N = 3). It has been effectively utilized for the detection of AFP in blood, providing a practical method for early detection and prevention of liver cancer, and also offering new insights for the design of other similar characteristic marker biosensors. [ABSTRACT FROM AUTHOR]

The swift progress in portable spectrometer technology has fostered a widespread need for compact light sources. Concurrently, near-infrared phosphor-converted light-emitting diodes (NIR pc-LEDs), characterized by their low cost and compact structure, emerge as an optimal choice. Inspired by phase optimization through fluxes, we successfully synthesized pure phase Lu 3 Mg 2 GaSi 2 O 12 (LMGS):Cr3+, 3 wt%MgF 2 luminescent materials by incorporating various fluxes including LiF, NaF, MgF 2 , CaF 2 , SrF 2 and BaF 2. These materials emit broadband NIR light ranging from 620 nm to 1150 nm, with full width at half-maximums (FWHMs) exceeding 125 nm. By employing a dual-fluxes strategy to further enhance the luminescence intensity of Cr3+, the LMGS:3%Cr3+, 1 wt%NaF, 2 wt%MgF 2 sample exhibits a 2.45 times increase in emission intensity compared to the LMGS:3%Cr3+, 3 wt%MgF 2 sample. Concurrently, the quantum efficiency rises from 24 % to 46 %. Moreover, the integrated emission intensity of LMGS:3%Cr3+, 1 wt%NaF, 2 wt%MgF 2 retains at 75 %@425 K of its value at RT. Upon coupled with a 430 nm LED chip, the luminescent material exhibits an NIR output power of 43.8 mW@300 mA, indicating promising applications in rapid night identification, night vision and non-destructive testing. By adding different fluxes, the luminescence intensity of LMGS:Cr3+ is achieved a stepwise enhancement. [Display omitted] [ABSTRACT FROM AUTHOR]

Near infrared spectroscopy is a simple, fast, and non-invasive technique for detecting the composition of substances. However, most NIR phosphors cannot cover the near-infrared I and II regions, which limits the types of substances that can be detected. Herein, Cr3+, Ni2+ co-activated NIR Y 3 Al 2 Ga 3 O 12 (YAGG) garnet phosphors were synthesized via high-temperature solid-phase method. Due to the energy transfer from Cr3+ to Ni2+, the emission spectra of YAGG: Cr3+, Ni2+ are composed of NIR I emission of Cr3+ at 710 nm and NIR II emission of Ni2+ at 1420 nm. The measured internal and external quantum efficiencies of YAGG: 0.08Cr3+, 0.005Ni2+ under 450 nm excitation are 54.4 %, and 26.7 %, respectively. This sample was selected to fabricate pc-LEDs, and fill the emission spectrum gap with Mg 2 GeO 4 : 0.01Cr3+. The pc-LED fabricated with PiG film do not exhibit strong characteristic absorption in NIR II region, significantly reduce the re-absorption and thermal quenching of the phosphors. The electro-optical conversion efficiency of PiG pc-LED reaches 6.49 % at 10 mA; The results indicate that YAGG: Cr3+, Ni2+ and the fabricated NIR pc-LED are good near-infrared substance detection light source scheme. [ABSTRACT FROM AUTHOR]

Using light as an external stimulus to control (bio)chemical processes offers many distinct advantages. Most importantly, it allows for spatiotemporal control simply through operating the light source. Photocleavable protecting groups (PPGs) are a cornerstone class of compounds that are used to achieve photocontrol over (bio)chemical processes. PPGs are able to release a payload of interest upon light irradiation. The successful application of PPGs hinges on their efficiency of payload release, captured in the uncaging Quantum Yield (QY). Heterolytic PPGs efficiently release low pKa payloads, but their efficiency drops significantly for payloads with higher pKa values, such as alcohols. For this reason, alcohols are usually attached to PPGs via a carbonate linker. The self‐immolative nature of the carbonate linker results in concurrent release of CO2 with the alcohol payload upon irradiation. We introduce herein novel PPGs containing sulfites as self‐immolative linkers for photocaged alcohol payloads, for which we discovered that the release of the alcohol proceeds with higher uncaging QY than an identical payload released from a carbonate‐linked PPG. Furthermore, we demonstrate that uncaging of the sulfite‐linked PPGs results in the release of SO2 and show that the sulfite linker improves water solubility as compared to the carbonate‐based systems. [ABSTRACT FROM AUTHOR]

To develop continuous broadband emission near-infrared (NIR) phosphors compatible with blue LED chips, numerous Cr3+-Yb3+ co-doped phosphors have been synthesized. However, the emission spectra of Cr3+ vary significantly across different matrix materials, while Yb3+ maintains a relatively stable emission spectrum. This variation leads to notable luminescence depressions between 850 and 900 nm in many Cr3+-Yb3+ co-doped phosphors. To address this emission spectrum gap, we utilized Cr3+ as a sensitizer and introduced Nd3+ as the luminescence center within the La 3 Sc 2 Ga 3 O 12 matrix material, establishing a Cr3+-Nd3+ energy transfer channel. Under 480 nm excitation, we tuned emission peaks at 800 nm (Cr3+) and 881 nm (Nd3+). The stable NIR emission of Nd3+ effectively compensates for the missing spectrum in Cr3+-Yb3+ co-doping. The Cr3+-Nd3+ energy transfer process was thoroughly analyzed using diffuse reflection spectrum, excitation spectrum, and fluorescence decay curves. The LSGO:0.125Cr3+, 0.03Nd3+ compound with the best optical performance was packaged with a 480 nm LED chip to create a NIR light source. At a working current of 10 mA, it achieved a photoelectric conversion efficiency of 9.45 %, demonstrating its potential for applications in non-destructive detection and luminescence thermometry. This work presents a novel strategy for tuning NIR spectral distribution and developing continuous broadband NIR phosphors. [ABSTRACT FROM AUTHOR]

Textile-based SrAl 2 O 4 (SAO): Eu2+, Dy3+ composite material offers functional, aesthetic, and safety benefits, making it a valuable innovation with diverse applications in various industries. The susceptibility of textile-based SAO: Eu2+, Dy3+ composite material is degraded with repeated washing, which can diminish its luminescent properties over time. Our major goal was to create a cloth with durable photoluminescent qualities by incorporating waterborne polyurethane (WPU) as a protective coating that could generate light constantly without a light source. Through a systematic approach involving the synthesis of photoluminescent SAO: Eu2+, Dy3+ particles and their integration into a cloth substrate with waterborne polyurethane, a durable cloth with enhanced durability, protection, and adhesion properties are achieved. Cotton fabric and a rotary screen-printing machine were used to apply a thin, translucent layer of glow-in-the-dark pigment to produce the photoluminescence characteristics of the developed cloth revealing efficient light absorption and emission behavior, with emission spectra centered around absorption wavelength between 560 nm and 880 nm, with a 500 nm emission peak, exhibiting of the presence of Eu2+ and Dy3+ activator ions. In addition, to assess the comfort of the treated cotton fabric, a fabroOmeter test was conducted, that provided insights into its overall comfort level. Furthermore, the cloth demonstrates excellent stability and longevity of photoluminescence under various environmental conditions, making it suitable for applications requiring high visibility, safety signage, decorative elements, and apparel wear. This research underscores the potential of polyurethane-enhanced photoluminescent textiles as versatile and sustainable solutions for diverse practical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Accurately estimating leaf chlorophyll concentrations in a three-dimensional (3D) manner is crucial for precisely monitoring crop growth and development. To reduce destructive detection and achieve real-time estimation, researchers often utilize crop leaves' SPAD (Soil and Plant Analyzer Development) to represent relative chlorophyll content. However, SPAD measurement is time-consuming and laborious work. Many inversion methods have been proposed to estimate SPAD based on one-dimensional reflectance or two-dimensional spectral images, which rely on external light sources and also cannot obtain 3D distribution. Hyperspectral LiDAR (HSL), as an active remote sensing technology, can acquire target spatial and spectral data simultaneously, making 3D SPAD inversion and reconstruction possible. This research aims to invert SPAD values with HSL spectral information aided by the PROSPECT model and reconstruct 3D SPAD distribution with HSL spatial information. Firstly, we constructed new ratio chlorophyll indices (RCI) based on the multi-feature analysis method with the PROSPECT model and HSL spectral data. Next, we employed RCIs to modify the Look-Up Table (LUT) cost function (SPAD-LUT) of the PROSPECT model, which was validated with the ANGERS dataset. Then, we conducted SPAD inversion with HSL spectral information from vegetable crop samples and integrated the inverted SPAD values into their corresponding 3D coordinates, achieving 3D SPAD distribution reconstruction. The predicted values of the model inversion with the HSL dataset are consistent with the measured SPAD (R2 = 0.421, RMSE = 10.615). The results indicate that our method can invert sample SPAD values and reconstruct their distribution with HSL point cloud despite their complex spatial structure. [ABSTRACT FROM AUTHOR]

White light-emitting diodes (WLEDs) represent a revolutionary type of energy-saving and environmentally friendly light source, which has been extensively employed in a multitude of lighting and display applications. Nevertheless, traditional organic packaging is unable to fulfill the requirements of highly reliable high-power WLEDs, including hemertic property, heat resistance, and excellent luminous properties. Herein, an all-inorganic hermetic packaging based on laser-localized welding and phosphor-in-glass film sintered on a sapphire lens (PiGF-SL) has been developed for high-power WLEDs. The PiGF-SL with a Kovar frame was welded to a three-dimensional direct-plated ceramic (3D-DPC). The high-strength and crack-free welded joint with a shear strength of 258.83 MPa and packaging cavity with excellent gas tightness (leakage rate 8.6 × 10−10 Pa m3/s) were simultaneously obtained, resulting in the high-power WLED capable of maintaining its excellent optical properties for an extended period in harsh environments. Furthermore, the optical performance of welded WLEDs was optimized by adjusting the PiGF-SL film thickness and red CaAlSiN3:Eu2+ (CASN) phosphor content. The welded WLED emits a cool white light by improving the PiGF thickness to 91 μm and exhibits high color quality with red CASN phosphor content of 8 wt%, which simultaneously presents outstanding color rendering index (CRI) of 91, luminous efficacy (LE) of 44.8 lm/W, and correlated color temperature (CCT) of 4322 K. Following a 200-h aging process, the laser-welded PiGF-SL-based WLED exhibited a slightly reduced efficiency loss and a stable color quality in comparison to reflow-soldered and epoxy-bonded WLEDs. Our work provides valuable guidance and solutions for the highly reliable and board-level packaging of WLEDs. [ABSTRACT FROM AUTHOR]

Benefitting from the mature, cost‐effective, and scalable manufacturing capabilities of complementary metal‐oxide‐semiconductor (CMOS) technology, silicon photonics has facilitated the seamless and monolithic integration of diverse functionalities, including optical sources, modulators, and photodetectors. Microresonators can generate multiple coherent optical frequency comb lines and serve as optical sources. However, at the telecom band, silicon suffers from two‐photon absorption and free‐carrier absorption, which severely hampers the realization of microcombs from a single silicon chip at telecom wavelengths until now. In this paper, a novel approach is presented and demonstrated with near‐infrared dual‐band frequency combs from a multimode silicon resonator. With a single pumping configuration, dual‐band combs are generated from the interaction between the pump and Raman Stokes fields by involving two different optical mode families but with similar group velocities. It is observed that the pump power required to generate dual‐band combs is as low as 0.7 mW. The work in bringing telecom microcombs to the silicon platform will advance silicon photonics for the next generation of monolithically integrated technology based on a single silicon chip, enabling new possibilities for further exploring silicon photonics‐based applications in optical telecommunications, sensing, and quantum metrology in the telecom band using a monolithic single silicon chip. [ABSTRACT FROM AUTHOR]

Accurate quantification of efficiency enables rigorous comparison between different photoluminescent materials, providing an optimization path critical to the development of next‐generation light sources. Persistent luminescent materials exhibit delayed and long‐lasting luminescence due to the temporary storage of optical energy in engineered structural defects. Standard characterization methods do not provide a universal comparison of phosphor performance, hindering the evaluation of the efficiency of the various processes involved in afterglow. Here, a protocol is established to determine the quantum yield of persistent phosphors by considering the ratio of photons emitted in the afterglow and during charging to those absorbed. The method is first applied to transparent single crystals of the most common persistent phosphors, such as SrAl2O4:Eu2+,Dy3+ and Y3Al2Ga3O12:Ce3+,Cr3+. The versatility of the methodology is demonstrated by quantifying the quantum yield of a ZnGa2O4:Cr3+ thin film, a material widely used in in vivo imaging. The high efficiency of strontium aluminate is confirmed, and a strong dependence of the obtained values on the illumination conditions is revealed, highlighting a trade‐off between efficiency and brightness. The results contribute to the development of standardized protocols for analyzing afterglow mechanisms and assessing overall efficiency, facilitating rigorous comparison and optimization of persistent materials beyond trial‐and‐error approaches. [ABSTRACT FROM AUTHOR]

Frontier scientific discoveries increasingly rely on big-science research infrastructures, such as supercolliders, synchrotron light sources, and space telescopes, whose construction and operation involve intensive international collaboration. This collaborative nature, however, presents a challenge in balancing national interests with the common good, particularly given the substantial fiscal investments involved. This study investigates the effects of one of China's prominent big-science infrastructures, the Shanghai Synchrotron Radiation Facility (SSRF), on the country's production of science, differentiating between national and international scientific endeavors. Employing a rigorous difference-in-differences (DID) methodology, it evaluates SSRF's effects on discipline-level production of publications by domestic researchers and those involving international collaboration. The empirical findings reveal compelling evidence that SSRF has significantly enhanced the production of high-impact national and international publications for disciplines reliant on the facility for experiments, particularly increasing the percentage of high-impact national publications. The findings also underscore the dual role of big-science infrastructures in fostering international research collaboration while simultaneously enhancing nations' domestic scientific development and competitiveness. Additionally, the study provides valuable insights for research assessment and science policy discussions. [ABSTRACT FROM AUTHOR]

Soft materials that respond to external stimuli are promising candidates for next-generation actuators with human-friendly nature1,2. Among various stimuli to induce strain, light offers spatial selectivity, which allows versatile motion of a continuous body. However, spatial selectivity of photoactuation has been limited in two dimension due to the predominant absorption of photons by chromophores near a light source in accordance with Beer-Lambert law. Here, we report the deformation of crosslinked liquid-crystalline polymer films triggered by two-photon absorption. The films containing azotolane moieties show photoinduced deformation upon irradiation with fs laser pulses through two-photon absorption. The direction of photoinduced bending is controlled by depth-selective excitation with a focused laser beam. Furthermore, the mode of deformation is transformed from bending to twisting by irradiating spots near an edge of the film. Inhomogeneous photoirradiation with high spatial selectivity allows an infinite variation of three-dimensional motions even apart from preprogrammed behavior, which would be advantageous especially in application to microactuators. Spatial selectivity of photoactuation in soft material has been limited in two dimension and three-dimensionally selective actuation is an effective approach to control the direction and types of macroscopic motions. Here, the authors report the photoinduced deformation of liquid-crystalline polymer films with high spatial selectivity via a two-photon absorption process. [ABSTRACT FROM AUTHOR]

The simulation and modelling of tree growth is a complex subject with a long history and an important area of research in both computer graphics and botany. For more than 50 years, new approaches to this topic have been presented frequently, including several aspects to increase realism. To further improve these achievements, we present a compact and robust functional‐structural plant model (FSPM) that is consistent with botanical rules. While we show several extensions to typical approaches, we focus mainly on the distribution of light as a resource in three‐dimensional space. We therefore present four different light distribution models based on ray tracing, space colonization, voxel‐based approaches and bounding volumes. By simulating individual light sources, we were able to create a more specified scene setup for plant simulation than it has been presented in the past. By taking into account such a more accurate distribution of light in the environment, this technique is capable of modelling realistic and diverse tree models. [ABSTRACT FROM AUTHOR]

We have explored the possibility of forming H⋅ and H 2 from H 2 S, CH 4 , H 2 O and SiH 4 in a series of ab initio calculations. The key finding is that H 2 S can give rise to direct photolytic ultrafast formation of H 2 This finding is in agreement with the available experimental data and is a result of a directed pathway that leads toward H 2 formation at easily accessible wavelengths. It arises at the (conical) intersection between the two lowest-lying electronic states. This intersection is a result of the valence orbital interaction of the two hydrogen atoms. This interaction is becoming more favorable as the S-H bonds simultaneously becomes longer. The H-S σ-σ∗ bonding interaction cannot compete with the bond formation that takes place between the hydrogens as two bonds stretch simultaneously. For oxygen this interaction it predominant. The reason is that sulfur has a higher principal quantum number and the interaction with the 1s of hydrogen therefore is less favorable. The excited states that are involved in the H 2 formation from H 2 S could be populated by, for example, a two-photon 400 nm excitation. The other hydrides have a more entangled potential energy landscape close to the Franck-Condon region in the direction of the reaction coordinate that leads to H 2 loss and as a result the direct loss of a hydrogen atom is favored. A two-photon excitation could be induced by femtosecond laser pulses that at the same time is proposed as a future platform for sensing the H 2 S molecules with the backward transient absorption scheme. The implication would be that both sensing and photoinduced H 2 formation could be in place at the same time which justifies the use of expensive femtosecond light sources getting "two for the price of one". • H 2 S can form H 2 when exposed to two 400 nm photons. • Interaction with short light pulses is predicted in induce non-statistical dynamics in H 2 S and H 2 O. • The findings could be a platform for sensing the H 2 S molecules with the backwards transient absorption scheme. [ABSTRACT FROM AUTHOR]

The relative fluorescence intensity from different multi-photon processes is affected by the excitation light source fluctuation, which reduces the anti-interference and sensitivity of thermometers based on fluorescence intensity ratio (FIR) in upconversion (UC) luminescence. Ca 1-x Mg x WO 4 : Yb3+, Er3+ phosphors with scheelite structure were synthesized to investigate their anti-interference and higher temperature sensitivity. With x increasing from 0 to 1, the Bragg angle shifted toward higher angle, indicating that the larger disorders were introduced into the phosphors. The emissions assigned to Er3+ were enhanced with Mg2+ concentration increasing, attributed to oxygen vacancies according to the results of electron paramagnetic resonance. The photon numbers of upconversion luminescence assigned to 2H 11/2 → 4I 15/2 , 4S 3/2 → 4I 15/2 and 4F 9/2 → 4I 15/2 transitions of Er3+ were three- and two-photon processes, respectively. The ratio between the cube of 4S 3/2 and the square of 2H 11/2 emissions revealed higher temperature sensing performance and anti-interference on the excitation source power than the that between 4S 3/2 and 2H 11/2. The maximum relative sensitivity was 0.66 % K−1 at 300 K based on the common optical ratiometric thermometry. The maximum relative sensitivity based on the emissions assigned to different multi-photon processes was 7.2 % K−1 at 573 K. The dopants of Mg2+ composited of oxygen vacancies in CaWO 4 crystals improved the luminous intensity and temperature sensing performance. This suggested the potential application of optical ratiometric thermometers based on different multi-photons of UC luminescence in temperature sensing field. [ABSTRACT FROM AUTHOR]

Upgrades to advanced scientific user facilities such as next-generation x-ray light sources, nanoscience centers, and neutron facilities are revolutionizing our understanding of materials across the spectrum of the physical sciences, from life sciences to microelectronics. However, these facility and instrument upgrades come with a significant increase in complexity. Driven by more exacting scientific needs, instruments and experiments become more intricate each year. This increased operational complexity makes it ever more challenging for domain scientists to design experiments that effectively leverage the capabilities of and operate on these advanced instruments. Large language models (LLMs) can perform complex information retrieval, assist in knowledge-intensive tasks across applications, and provide guidance on tool usage. Using x-ray light sources, leadership computing, and nanoscience centers as representative examples, we describe preliminary experiments with a Context-Aware Language Model for Science (CALMS) to assist scientists with instrument operations and complex experimentation. With the ability to retrieve relevant information from facility documentation, CALMS can answer simple questions on scientific capabilities and other operational procedures. With the ability to interface with software tools and experimental hardware, CALMS can conversationally operate scientific instruments. By making information more accessible and acting on user needs, LLMs could expand and diversify scientific facilities' users and accelerate scientific output. [ABSTRACT FROM AUTHOR]

Photon‐pair generation based on optical parametric down‐conversion has attracted for the application as a light source for quantum information. Highly efficient wavelength‐conversion devices require a polarity‐inversion structure when using nitride semiconductors. A transverse quasi‐phase‐matching (QPM) polarity‐inverted GaN bilayer channel waveguide device is suitable for efficient wavelength conversion. This study designed a cross‐section device to satisfy the modal dispersion phase‐matching condition between the TM02 mode pump light and the TM00 mode signal/idler light. Moreover, an AlN oxidation interlayer fabricates the Ga‐polar/N‐polar (+c/−c) GaN layers via metalorganic vapor‐phase epitaxy (MOVPE). A 145 nm thick film layer with a macro‐step‐free surface is grown by optimizing the −c‐GaN growth conditions and reducing the substrate off‐angle to 0.2°. Next, the AlN layer is oxidized in an electric furnace and MOVPE is used to regrow a 1500 nm thick +c‐GaN layer. A macrosteps‐free surface can be achieved by reducing the off‐angle to 0.2° and optimizing the −c‐GaN growth conditions to avoid hillock formation. These results pave the way for improving the efficiency of GaN transverse QPM wavelength‐conversion devices. [ABSTRACT FROM AUTHOR]

Genetic engineering faces persistent challenges in achieving precise Deoxyribonucleic acid (DNA) cleavage, especially with the limitations associated with current enzyme‐based methods, exemplified by issues in CRISPR technologies. This study introduces a groundbreaking approach: utilizing reactive oxygen species (ROS) generated by Multiphoton Absorption (MPA)‐excited Black Phosphorus Quantum Dots (BPQDs) under femto‐second laser irradiation. This innovative method not only allows excitation with lower energy but also enhances overall efficiency. The integration of complementary RNA sequences facilitates high‐efficiency, site‐selective DNA cleavage in the system, named "TADPOLE" (Targeted DNA Precision Oriented Laser Excision). Beyond its precision in targeting arbitrary DNA sequences using quantum dots, TADPOLE harnesses the unique multiphoton absorption property of BPQDs, enabling excitation with lower‐energy light sources suitable for in vivo applications in the future. Moreover, the approach integrates guiding RNA and ultrafast laser technology to provide precise control over local ROS generation and minimal heat production. This guarantees site‐specific DNA cleavage while mitigating the risk of damage to non‐targeted sequences. In summary, this study catalyzes advancements in enzyme‐free DNA cleavage technologies, with transformative implications for genetic engineering, biotechnology, and medicine. The holistic precision, versatility, and endurance presented by TADPOLE open new avenues for targeted gene therapies and transformative applications in related fields. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) phosphor‐converted light‐emitting diode (pc‐LED) light sources in the second NIR window (NIR‐II, 1000–1700 nm) have sparked great interest for their emerging applications in non‐destructive detection and medical diagnostics fields. However, the development of efficient NIR‐II phosphors that can be excited by commercial blue LED chips remains a significant challenge, and thus impeding the applications of NIR pc‐LED. Herein, a blue‐light‐excitable broadband NIR‐II luminescence of Ni2+ is achieved upon incorporating Cr3+ and Ni2+ into the Ca3Ga2Ge3O12 (CGGO) host simultaneously. Through the energy transfer from Cr3+ to Ni2+, CGGO:Cr3+,Ni2+ phosphor presents the improved NIR‐II emission peaking at 1470 nm under 460 nm blue light excitation. The internal/external quantum efficiency values are significantly improved from 13.8%/3.3% to 24.6%/13.3% along with the enhanced luminescence thermal stability. Finally, a NIR pc‐LED is fabricated by combining CGGO:Cr3+,Ni2+ phosphor with 450 nm blue chip, and its potential applications in non‐destructive examination and biomedical imaging fields have been demonstrated. The strategy of Cr3+ and Ni2+ co‐doping solves the problem that Ni2+ luminescence cannot be effectively excited by blue light and provides the design insights to exploit more ultra‐broadband NIR pc‐LEDs based on blue LED chips. [ABSTRACT FROM AUTHOR]

The phantom array effect (PAE) is a series of repeated images that may be perceived when a person moves their eyes in large saccades across a light source (or a specular reflection of that light source) that is modulating in output over time. Fifty-five people, including a group of 25 who experience migraine, evaluated the visibility and annoyingness of phantom arrays produced by 85 unique temporal light modulation waveforms (including sine, rectangular, complex and DC waveforms) generated using an LED placed against a black background. Those with migraine exhibited higher average visibility compared to those without migraine (p = 0.019) and were relatively more sensitive at higher frequencies (p < 0.001). Younger participants also found more stimuli to be visible (p < 0.001). The threshold sensitivity function was similar to that developed for the phantom array visibility measure (PAVM), and PAVM was effective in predicting visibility (R 2 = 0.87 for the relevant region of PAVM < 3). While those in the migraine group did not report seeing the PAE more often in everyday life at a statistically significant level, they reported being more annoyed by it and having more unwanted physiological responses (headaches, eye fatigue and distraction/disorientation). Members of the migraine group were also more likely to have changed their behaviour in architectural spaces (such as leaving a restaurant with 'flickering' lights). In the four hours after completing the experiment, 64% of the migraine group (vs. 19% of the non-migraine group) reported experiencing discomfort or an adverse reaction. In particular, 41% reported experiencing a headache (vs. 8% for those in the non-migraine group). [ABSTRACT FROM AUTHOR]

At temporal light modulation (TLM) frequencies between 80 Hz and 20 000 Hz observers may perceive a series of repeated images called the phantom array effect (PAE) when they move their eyes in large saccades across a modulating light source or across a scene lit by the modulating light source. To date, there is no well-established measure for quantifying PAE visibility, but there is growing awareness of the need for one among design professionals and sensitive populations. This paper documents a new measure, the phantom array visibility measure (PAVM), which is based on the results of recent human factors experiments. The measure follows the mathematical underpinning used by the flicker visibility measure and the stroboscopic visibility measure, where the time-domain TLM waveform is converted into its Fourier frequency components; each component is evaluated through a threshold curve of modulation depth, then summed through an equation employing a Minkowski exponent. This scales the PAVM so that a value of 1 indicates a waveform at a threshold visibility in the conditions of the underlying experiment. [ABSTRACT FROM AUTHOR]

Flicker and stroboscopic effects caused by a temporally modulated light source may be harmful for the human visual system. Standardized measurement methods have been developed for the related temporal light artefacts of LED luminaires. It was found out that the performance of the International Electrotechnical Commission (IEC) recommended flickermeter implementation is highly dependent on sampling frequency. Novel digital implementations for the flickermeter and stroboscopic effect visibility measure (SVM) were created to remove any inaccuracies. The performance of the novel Aalto implementations does not depend on the sampling frequency when running the test waveforms of the IEC standard through the implementations. As compared with the IEC recommended digital implementations, Aalto flickermeter decreases the average error related to the test waveforms from −0.05 to +0.003, and Aalto SVM meter also decreases the average error by almost two orders of magnitude. [ABSTRACT FROM AUTHOR]

Solid-state light sources can be more prone to larger temporal light modulation (TLM) than conventional sources. TLM visibility depends on wave shape, frequency, modulation depth and duty cycle, and is affected by the sensitivity of the observer. TLM can be visible well above the critical flicker fusion frequency, when there is relative movement between the observer's eyes and light source, lighted space or moving objects in the field of view. This human subjects experiment explored visibility of the stroboscopic effect (SE) versus the phantom array effect (PAE) with targeted tasks under 74 TLM waveforms. The results showed the SE visibility peaks between 90 Hz and 120 Hz, while the PAE visibility peaks between 500 Hz and 1000 Hz. The phantom array is visible to sensitive participants at 6000 Hz. Both effects are more visible under rectangular versus sinusoidal TLM, higher modulation, and when duty cycles are 10% or 30% versus 50%. Higher sensitivity participants, differentiated using the Leiden Visual Sensitivity Scale, rated TLM waveforms as more visible, especially those inherently harder to see. This work lays a foundation for a PAE metric and guides driver and dimmer designers toward electronic circuits that minimize the visibility of TLM in LED products. [ABSTRACT FROM AUTHOR]

A phantom array can be observed when there are saccadic eye movements across a time-modulated light source. In this study, the highest frequency limit of the phantom array effect that can be observed was investigated using an LED light source by estimating the participant's threshold frequency for the visibility of the phantom array effect using the weighted up-down method. A high luminance, narrow slit, warm white LED, and long saccadic eye movement range were used as the experimental stimuli and conditions. The mean threshold frequency for young adults was approximately 10 kHz under the proposed experimental conditions. The phantom array effect was observed even above 15 kHz in the high threshold frequency group when we divided participants into three groups according to the threshold frequency. In addition, the high threshold frequency group showed a higher eye movement speed than the other groups. [ABSTRACT FROM AUTHOR]

Spontaneously integrated multicolor InGaN micro‐light‐emitting diodes with a microstripe topography achieve selective electrical operation with four different color emissions: green, bluish‐green, bluish‐purple, and purple. The entire microstripe displays broadband emissions because the stripe topography with a convex lens‐like cross section induces a continuous emission wavelength gradient in the overgrown InGaN active layers. Since each wavelength component is distributed along the stripe direction, multiple narrow p‐electrodes are positioned side by side across the stripe width. This design supports selective current injection into the corresponding local areas. This work represents an important step for realizing broadband visible light emitters where individual wavelength components comprising the broad spectra can be modulated and switched independently. [ABSTRACT FROM AUTHOR]

In this review paper, information about bicycle lamp technical parameters is provided. The review is based on the searched Web of Science (WoS) and Scopus bibliographic databases and Transportation Research Information Services, which include references to books, technical reports, conference proceedings, and journal articles. This review showed that these papers about bicycle lighting legal rules in given countries are very easy to reach, but deep searching must be performed to find this research paper having the information about types of optical systems and light sources used in bicycle lamps. This research was conducted using PRISMA 2020 assumptions in the area of bicycle lighting technologies and innovations. The information about bicycle lamp technical parameters was obtained on the basis of the examination of technical documents and papers from high-impact journals. The author's review shows that contemporary bicycle lamps are becoming increasingly smarter and more energy efficient, while also enhancing safety and comfort for cyclists on their routes in and beyond urban environments. [ABSTRACT FROM AUTHOR]

Spectral tunable technology has to meet the requirements of strong robustness and wide spectral range. We propose a method for the transmission and manipulation of infrared topological photonic crystal valley states based on tunable refractive index method that exhibits broad-spectrum and multi-band characteristics, along with a tunable emission angle. With this structure, different rotational directions of vortex light sources can independently excite the K valley and K′ valley within the frequency band ranging from 75.64 THz to 99.61 THz. At frequencies from 142.60 THz to 171.12 THz, it is possible to simultaneously excite both the K valley and K′ valley. The dual refractive index tunable design allows for the adjustment of the emission angle at a fixed frequency, enabling control over the independent excitation of either a single K valley or K′ valley, as well as their simultaneous excitation. This capability has significant implications for photonic computation and tunable filtering, offering enhanced operational flexibility and expanded functionality for future optical communications and integrated optical circuits. [ABSTRACT FROM AUTHOR]

The design and first results of a high‐transmission soft X‐ray spectrometer operated at the X‐SPEC double‐undulator beamline of the KIT Light Source are presented. As a unique feature, particular emphasis was placed on optimizing the spectrometer transmission by maximizing the solid angle and the efficiencies of spectrometer gratings and detector. A CMOS detector, optimized for soft X‐rays, allows for quantum efficiencies of 90% or above over the full energy range of the spectrometer, while simultaneously offering short readout times. Combining an optimized control system at the X‐SPEC beamline with continuous energy scans (as opposed to step scans), the high transmission of the spectrometer, and the fast readout of the CMOS camera, enable the collection of entire rapid resonant inelastic soft X‐ray scattering maps in less than 1 min. Series of spectra at a fixed energy can be taken with a frequency of up to 5 Hz. Furthermore, the use of higher‐order reflections allows a very wide energy range (45 to 2000 eV) to be covered with only two blazed gratings, while keeping the efficiency high and the resolving power E/ΔE above 1500 and 3000 with low‐ and high‐energy gratings, respectively. [ABSTRACT FROM AUTHOR]

The upgrade of the Swiss Light Source, called SLS 2.0, necessitates comprehensive updates to all 18 user front ends. This upgrade is driven by the increased power of the synchrotron beam, reduced floor space, changing source points, new safety regulations and enhanced beam properties, including a brightness increase by up to a factor of 40. While some existing front‐end components are being thoroughly refurbished and upgraded for safety reasons, other components, especially those designed to tailor the new synchrotron beam, are being completely rebuilt. These new designs feature innovative and enhanced cooling systems to manage the high‐power load and meet new requirements such as mechanical stability and compact footprints. [ABSTRACT FROM AUTHOR]

Geological samples are inherently multi‐scale. Understanding their bulk physical and chemical properties requires characterization down to the nano‐scale. A powerful technique to study the three‐dimensional microstructure is X‐ray tomography, but it lacks information about the chemistry of samples. To develop a methodology for measuring the multi‐scale 3D microstructure of geological samples, correlative X‐ray micro‐ and nanotomography were performed on two rocks followed by scanning electron microscopy with energy‐dispersive spectroscopy (SEM‐EDS) analysis. The study was performed in five steps: (i) micro X‐ray tomography was performed on rock sample cores, (ii) samples for nanotomography were prepared using laser milling, (iii) nanotomography was performed on the milled sub‐samples, (iv) samples were mounted and polished for SEM analysis and (v) SEM imaging and compositional mapping was performed on micro and nanotomography samples for complimentary information. Correlative study performed on samples of serpentine and basalt revealed multiscale 3D structures involving both solid mineral phases and pore networks. Significant differences in the volume fraction of pores and mineral phases were also observed dependent on the imaging spatial resolution employed. This highlights the necessity for the application of such a multiscale approach for the characterization of complex aggregates such as rocks. Information acquired from the chemical mapping of different phases was also helpful in segmentation of phases that did not exhibit significant contrast in X‐ray imaging. Adoption of the protocol used in this study can be broadly applied to 3D imaging studies being performed at the Advanced Light Source and other user facilities. [ABSTRACT FROM AUTHOR]

VMXm joins the suite of operational macromolecular crystallography beamlines at Diamond Light Source. It has been designed to optimize rotation data collections from protein crystals less than 10 µm and down to below 1 µm in size. The beamline has a fully focused beam of 0.3 × 2.3 µm (vertical × horizontal) with a tuneable energy range (6–28 keV) and high flux (1.6 × 1012 photons s−1 at 12.5 keV). The crystals are housed within a vacuum chamber to minimize background scatter from air. Crystals are plunge‐cooled on cryo‐electron microscopy grids, allowing much of the liquid surrounding the crystals to be removed. These factors improve the signal‐to‐noise during data collection and the lifetime of the microcrystals can be prolonged by exploiting photoelectron escape. A novel in vacuo sample environment has been designed which also houses a scanning electron microscope to aid with sample visualization. This combination of features at VMXm allows measurements at the physical limits of X‐ray crystallography on biomacromolecules to be explored and exploited. [ABSTRACT FROM AUTHOR]

SPring‐8‐II is a major upgrade project of SPring‐8 that was inaugurated in October 1997 as a third‐generation synchrotron radiation light source. This upgrade project aims to achieve three goals simultaneously: achievement of excellent light source performance, refurbishment of aged systems, and significant reduction in power consumption for the entire facility. A small emittance of 50 pm rad will be achieved by (1) replacing the existing double‐bend lattice structure with a five‐bend achromat one, (2) lowering the stored beam energy from 8 to 6 GeV, (3) increasing the horizontal damping partition number from 1 to 1.3, and (4) enhancing horizontal radiation damping by installing damping wigglers in long straight sections. The use of short‐period in‐vacuum undulators allows ultrabrilliant X‐rays to be provided while keeping a high‐energy spectral range even at the reduced electron‐beam energy of 6 GeV. To reduce power consumption, the dedicated, aged injector system has been shut down and the high‐performance linear accelerator of SACLA, a compact X‐ray free‐electron laser (XFEL) facility, is used as the injector of the ring in a time‐shared manner. This allows the simultaneous operation of XFEL experiments at SACLA and full/top‐up injection of the electron beam into the ring. This paper overviews the concept of the SPring‐8‐II project, the system design of the light source and the details of the accelerator component design. [ABSTRACT FROM AUTHOR]

Here, a recently commissioned five‐analyzer Johann spectrometer at the Inner Shell Spectroscopy beamline (8‐ID) at the National Synchrotron Light Source II (NSLS‐II) is presented. Designed for hard X‐ray photon‐in/photon‐out spectroscopy, the spectrometer achieves a resolution in the 0.5–2 eV range, depending on the element and/or emission line, providing detailed insights into the local electronic and geometric structure of materials. It serves a diverse user community, including fields such as physical, chemical, biological, environmental and materials sciences. This article details the mechanical design, alignment procedures and data‐acquisition scheme of the spectrometer, with a particular focus on the continuous asynchronous data‐acquisition approach that significantly enhances experimental efficiency. [ABSTRACT FROM AUTHOR]

Conic sections are commonly used in reflective X‐ray optics. Hyperbolic mirrors can focus a converging light source and are frequently paired with elliptical or parabolic mirrors in Wolter type configurations. This paper derives the closed‐form expression for a mirror‐centered hyperbolic shape, with zero‐slope at the origin. Combined with the slope and curvature, such an expression facilitates metrology, manufacturing and mirror‐bending calculations. Previous works consider ellipses, parabolas, magnifying hyperbolas or employ lengthy approximations. Here, the exact shape function is given in terms of the mirror incidence angle and the source and image distances. [ABSTRACT FROM AUTHOR]

Autonomous methods to align beamlines can decrease the amount of time spent on diagnostics, and also uncover better global optima leading to better beam quality. The alignment of these beamlines is a high‐dimensional expensive‐to‐sample optimization problem involving the simultaneous treatment of many optical elements with correlated and nonlinear dynamics. Bayesian optimization is a strategy of efficient global optimization that has proved successful in similar regimes in a wide variety of beamline alignment applications, though it has typically been implemented for particular beamlines and optimization tasks. In this paper, we present a basic formulation of Bayesian inference and Gaussian process models as they relate to multi‐objective Bayesian optimization, as well as the practical challenges presented by beamline alignment. We show that the same general implementation of Bayesian optimization with special consideration for beamline alignment can quickly learn the dynamics of particular beamlines in an online fashion through hyperparameter fitting with no prior information. We present the implementation of a concise software framework for beamline alignment and test it on four different optimization problems for experiments on X‐ray beamlines at the National Synchrotron Light Source II and the Advanced Light Source, and an electron beam at the Accelerator Test Facility, along with benchmarking on a simulated digital twin. We discuss new applications of the framework, and the potential for a unified approach to beamline alignment at synchrotron facilities. [ABSTRACT FROM AUTHOR]

Nanoparticles particularly titanium dioxide (TiO2) have demonstrated remarkable potential in both photocatalytic degradation of the toxic compounds and development of the effective photodynamic therapy (PDT) by harnessing light-induced reactive oxygen species (ROS) generation. In PDT, the choice of appropriate photosensitizers (PSs) and optimal light sources is crucial for the therapeutic efficacy. Pure titanium dioxide has the drawbacks of limited tissue penetration and high cytotoxicity due to the triggered traditional ultraviolet light sources, rapid recombination rate of the electron (e−)/hole (h+) pairs attributed to their broader band gap energy, and low solubility with high tendency to aggregation in water. Reproducible synthesis and efficiency optimization in ROS generation are also among the challenges. Addressing these challenges, this study focuses on the construction of a novel PDT nanoplatform: design and synthesis of the biocompatible N-doped-TiO2/FeTCPP (PFNT) by modifying TiO2 nanoparticles with urea as a safe nitrogen source (NT) to create an efficient type I PS, which expands the optical absorption capacity between 400 and 800 nm due to the facilitated localized nitrogen states within the titanium dioxide band gap, as well as by incorporating iron metalloporphyrin FeTCPP (tetra(4-carboxyphenyl) porphyrin) as an effective type II PS. Upon visible-light irradiation, FeTCPP not only sensitizes singlet oxygen, but also transfers electrons from excited FeTCPP* species to Ti4+-based N-TiO2 to afford FeTCPP•+ ligands and Ti3+ centers, thus propagating the production of hydrogen peroxide, superoxide, and hydroxyl radicals. By generating the substantial distinct ROS, significant tumor cell killing was obtained under LED irradiation, particularly in addressing melanoma. This research underscores substantial promise of the designed N‐TiO2/FeTCPP nanocomposites in advancing the field of PDT-based cancer therapy, paving the way for efficient and targeted treatments. [ABSTRACT FROM AUTHOR]

Synthesized DE@HTDMS-SiO2 particles loaded with TiO2 nanoparticles, linked to adhesive epoxy resin and the green hydrophobic agent cetyltrimethoxysilane, were utilized to fabricate superhydrophobic composite coatings on various substrates using a simple spraying technique. The resulting composite coating exhibited a contact angle of 156.6° and a rolling angle of 7.6°, demonstrating excellent self-cleaning properties, antifouling capabilities, and durability. The photocatalytic performance was evaluated by using visible light from a 220 W incandescent lamp as a light source. The results indicated that the composite coating could degrade both RhB and MB solutions by over 90%. In a custom-made oil–water separation device, the composite-coated cotton fabric achieved a separation efficiency exceeding 96% for mixtures of n-hexane and diesel. Even after 10 cycles of repeated separation, the efficiency remained above 89%. This underscores the composite coating's remarkable photocatalytic performance and its capacity for efficient, recyclable oil–water separation. Furthermore, the hydrophobic angle of the composite superhydrophobic glass sheet decreased by only 2.3° after undergoing a three-month outdoor aging experiment. Additionally, the composite-coated cotton fabric maintained a certain level of hydrophobicity even after being submerged in a strong alkali solution for 24 h. [ABSTRACT FROM AUTHOR]

Individuals with Down syndrome are known to have a greater prevalence of ocular conditions such as strabismus, nystagmus, elevated refractive error, poor accommodative function, elevated higher‐order optical aberrations and corneal abnormalities. Related to these conditions, individuals with Down syndrome commonly have reduced best‐corrected visual acuity at both far and near viewing distances across their lifespan. This review summarises the various optical sources of visual acuity reduction in this population and describes clinical trials that have evaluated alternative spectacle prescribing strategies to minimise these optical deficits. Although refractive corrections may still have limitations in their ability to normalise visual acuity for individuals with Down syndrome, the current literature provides evidence for eye care practitioners to consider in their prescribing practices for this population to maximise visual acuity. These considerations include accounting for the presence of elevated higher‐order aberrations when determining refractive corrections and considering bifocal lens prescriptions, even for young children with Down syndrome. [ABSTRACT FROM AUTHOR]

Light-emitting diodes (LEDs) have revolutionized artificial lighting, but also exposed the detrimental health effects that stem from insufficient exposure to natural light. Human-centric artificial lighting requires both visual quality and circadian lighting performance that mimics daylight's evolving spectral power distribution (SPD). Here, we present a color-tunable LED-based light source that achieves SPDs similar to various conditions of daylight and incandescent lighting over the range of visible wavelengths. This light source is comprised of a linear combination of light converter channels containing dyes exhibiting thermally activated delayed fluorescence (TADF) fabricated through additive manufacturing, photoexcited by violet-emitting LEDs (VLED). This hybrid light source establishes a new benchmark for state-of-the-art artificial lighting at approximating daylight, with Illuminating Engineering Society (IES) color gamut index Rg values within 3%, IES color fidelity index Rf values within 7% through CCT values ranging from 4277 K to 22,333 K. We propose efficiency metrics to accurately quantify similarity between light sources and the respective reference daylight spectrum encompassing visual and circadian effects, facilitating WLED benchmarking. The efficiency metrics pertaining to circadian lighting performance remain within 10% over the same CCT range. These results advance lighting science to address simultaneously the grand challenges of health and sustainability. [ABSTRACT FROM AUTHOR]

The aerosol optical depth, as an aerosol optical property, is a key physical quantity used to characterize the degree of atmospheric turbidity. The radiance of the integrating sphere light source after radiometric calibration is relatively stable. Compared with the original use of city lights to invert the night-time aerosol optical depth (AOD), the use of the integrating sphere can effectively reduce the change of the emission source and improve the inversion accuracy. A model to retrieve night-time AOD based on combined measurements of satellite low light channels and ground-based integrating spheres was established by the night-time artificial observation experiment in the Dunhuang radiation correction field (DRCF) for 38 consecutive days from October to November 2018. After excluding cloud pollution and moonlight pollution, the calculated results are compared with the Moderate Resolution Imaging Spectroradiometer (MODIS) data and the Visible/Infrared Imaging Radiometer Suite (VIIRS) night-time aerosol data. The average root mean square error of the processed data is 0.11 and 0.23, and the correlation coefficient reaches 0.85 and 0.46, respectively. The experimental results preliminarily show that the retrieval AOD is in good agreement with the satellite data, and it is feasible to retrieve AOD based on combined measurements of satellite low light channels and ground-based integrating spheres. [ABSTRACT FROM AUTHOR]

The Chinese Academy of Engineering Physics Terahertz Free Electron Laser Facility (CAEP THz FEL, CTFEL) is the only high-average power free electron laser terahertz source based on superconducting accelerators in China. The update of the CTFEL is now undergoing and will expand the frequency range from 0.1–4.2 THz to 0.1–125 THz. Two experimental stations for material spectroscopy and biomedicine will be built. A high harmonic generation (HHG) lightsource based beamline at the material spectroscopy experimental station for time-resolved angle-resolved photoemission spectroscopy (ARPES) research will be constructed and the optical design is presented. The HHG lightsource covers the extreme ultraviolet (XUV) photon energy range of 20–50 eV. A Czerny–Turner monochromator with two plane gratings worked in conical diffraction configuration is employed to maintain the transmission efficiency and preserve the pulse time duration. The calculated beamline transmission efficiency is better than 5% in the whole photon energy range. To our knowledge, this is the first time in China to combine THz-infrared FEL with HHG light source, and this experimental station will be a powerful and effective instrument that will give new research opportunities in the future for users doing research on the dynamic evolution of the excited electron band structure of a material's surface. [ABSTRACT FROM AUTHOR]

Photosensitive glass-ceramics exhibit significant potential to replace silicon materials in the microfabrication of micro-electro-mechanical-system (MEMS) devices. However, they are constrained by the limitations of a conventional 320-nm photolithography process. Therefore, developing an ideal industrial i-line (365 nm) photolithography for Li 2 O–Al 2 O 3 –SiO 2 photosensitive glass-ceramics is urgently needed. This study initially explores the impact of a facile i-line photolithography on the structure and physicochemical properties of photosensitive glass ceramics. We experimentally showcase a direct, scalable, and straightforward i-line photolithography technique for Li 2 O–Al 2 O 3 –SiO 2 photosensitive glass ceramics. Our research concentrates on how the exposure time affects the properties of Li 2 O–Al 2 O 3 –SiO 2 photosensitive glass ceramics, particularly regarding nucleation and crystallization. This is achieved by adjusting the exposure time parameter and utilizing XRD, etching experiments, SEM, TEM, and other tests under a i-line light source. By optimizing the exposure process parameters, we also modify the annealing process parameters affecting the crystallization of lithium metasilicate in the exposed areas. Under a treatment process involving an exposure time of 20 min, a nucleation temperature of 500 °C, a crystallization temperature of 630 °C, and a nucleation/crystallization duration of 2 h, the sample achieves the highest crystal quantity and the optimal thickness-etching rate ratio. [ABSTRACT FROM AUTHOR]

Heterojunctions formed between undoped and Eu‐doped NiO nanofibers (NFs) and n‐Si were fabricated by electrospinning the NiO:Eu NFs onto Si. Since the photoresponse of the Eu‐doped NiO‐containing device was better than the undoped one, the study focused on the doped NiO‐containing device. This was explained by the increase in electron kinetics in terms of the active role of Eu in bonding with the 4f orbitals and the s, d, and f states of NiO. Electro‐optical measurements of the NiO:Eu NFs/n‐Si heterojunction were performed in the visible region depending on the light intensity and in the UV and NIR regions for 10 mW/cm2 powers. It was observed that the device exhibits a good level of rectification properties and responds very well to all lights. At all three light sources, the heterojunction photodetector exhibited self‐powered behavior. Furthermore, for 10 mW/cm2 light intensity, the NiO:Eu NFs/n‐Si photodetector achieved R values of 1.84 A/W at 365 nm, 0.98 A/W at 395 nm, and 1.54 A/W at 850 nm, while it is 0.12 A/W for visible light. Besides, the device showed an external quantum efficiency of 625% and this was attributed to the photocurrent gain. In self‐driven mode, D* values have been determined as 3.0 × 1012 Jones, 2.6 × 1012 Jones, and 2.9 × 1012 Jones for 365, 395, and 850 nm, respectively. The performance of NiO under UV light was attributed to the absorption of NiO under UV light, as well as the very good excitation of (Eu3+) ions by UV light. [ABSTRACT FROM AUTHOR]