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Light‐sheet microscopy stands out as a powerful tool in biological imaging due to its exceptional performance in fluorescence imaging. However, achieving both high sectioning performance and a vast field of view (FOV) poses a fundamental challenge in conventional light‐sheet microscopy. The light‐sheet thickness is typically constrained to 1 µm for a wide FOV, potentially compromising resolution. To address this limitation, an axial scanning light‐sheet microscopy (ASLM) technique integrated with aberration‐free tunable foci to enable high‐NA excitation while maintaining a generous FOV, is introduced. The proposed scheme successfully achieves isotropic resolution of 280 nm in a 3D imaging system, encompassing a FOV of 80 × 80 µm and an impressive imaging speed of 80 ms per frame. These remarkable characteristics underscore the immense potential of ASLM for high‐ spatiotemporal resolution imaging. [ABSTRACT FROM AUTHOR]

Maintaining a thermally comfortable living and working environment with renewable energy sources is crucial for human health. However, achieving temperature self-regulation in individual textiles without external interventions remains a challenge. Here, we present a dual-modal photonic textile capable of autonomously achieving both low-temperature solar heating and high-temperature radiative cooling under sunlight. This innovative textile is primarily composed of textile fibers that are functionalized with thermochromic microcapsules encapsulated in graphene and barium sulfate coatings, which exhibit approximately 80% visible light optical modulation when integrated into the fabric. We demonstrate that garment and tent (3.5 m × 2.9 m × 1.3 m) fabricated from these textiles can achieve temperature-adaptive, all-weather thermal management, expanding the thermal comfort range by 8.5°C. This research showcases notable potential for applications in fabric-related heat management and highlights the importance of exploring temperature-adaptive solutions for a sustainable and healthy lifestyle. [ABSTRACT FROM AUTHOR]

Vectorial holography technology plays a fundamental role by exploring the vectorial nature of light and enriches disruptive applications in optical encryption, display, and manipulation. With its flexible control methods and high‐precision subwavelength design, metasurface possesses rich modulation flexibility that surpasses traditional optical modulation devices. Here, a vectorial holographic design is implemented that can cover various polarization information by using a birefringent metasurface. The design adopts a gradient descent optimization method to jointly optimize the phase information of the orthogonal polarization channels with the birefringent metasurface, for continuous variation of polarization information in the entire vector space on the Poincare Sphere with efficient information integration. Based on the detailed depiction of full vector space polarization texture, such efficient vectorial holographic optimization methods can expand the encryption channels and achieve high spatial resolution allowing large capacity multiplexing, data storage, pattern recognition, etc. [ABSTRACT FROM AUTHOR]

An efficiency of delocalization in strongly conjugated systems remains an important factor crucial for modulation of the optical properties directly correlated with its range. An ortho‐substituted phenylene derivative bearing electron donating/accepting functionality was built‐in a fully unsaturated macrocyclic system with a global delocalization of a diatropic and/or a paratropic current. A precisely located structural modification influence observed behaviour in spectroscopic parameters that are only slightly recognizable in 4n+2 systems but showing a significant influence on the reduced derivatives with a contribution of 4n π‐electrons delocalization path. [ABSTRACT FROM AUTHOR]

We report the design, synthesis, photoswitching and computational studies of N-methyl arylazo-3,5-(di-2-pyridyl)pyrazole and its N-alkyl pyridinium derivatives with an ionic center proximally located to the azo group. Besides achieving excellent photoswitching characteristics, particularly at longer wavelengths, and tuning Z isomer stability due to the effects of counter ions and pH, the utility of neutral and ionic photoswitches for pH modulation by light was achieved. [ABSTRACT FROM AUTHOR]

Future wireless networks extensively employ the two-dimensional Optical-Orthogonal Time Frequency Space (O-OTFS) modulation system due to its increased dependability, flexibility, and data throughput. When there is a lot of movement, OTFS offers improved connectivity performance. While OFDM functions in the time-frequency domain, O-OTFS modulation acts in the delay-Doppler domain. This study provides an overview of how OTFS functions in the delay-Doppler domain, as well as its benefits and drawbacks. Next-generation networks utilize this modulation method in various applications, such as vehicle-to-vehicle communication, communication in mountainous areas, high-speed mobility, and train communication. This paper provides an easy-to-understand overview of the PAPR algorithms and its reduction in O-OTFS modulation. [ABSTRACT FROM AUTHOR]

Spherical quantum wells (SQWs) have proven to be excellent materials for suppressing Auger recombination due to their expanded confinement volume. However, research on the factors and mechanisms of their high-intensity optical properties, such as multiexciton properties and third-order optical nonlinearities, remains incomplete, limiting further optimization of these properties. Here, a series of CdS/CdSe (xML)/CdS SQWs with varying CdSe layer thicknesses were prepared. The modulation effects of CdSe shell variations on the PL properties, defect distribution, biexciton binding energy, and third-order optical nonlinearities of the SQWs were investigated, and their impact on the material's multiexciton properties was further analyzed. Results showed that the typical CdS/CdSe(3ML)/CdS sample exhibited a large volume-normalized two-photon absorption cross-section (18.17 × 102 GM/nm3) and favorable biexciton characteristics. Optical amplification was observed at 12.4 μJ/cm2 and 1.02 mJ/cm2 under one-photon (400 nm) and two-photon (800 nm) excitation, respectively. Furthermore, different amplified spontaneous emission spectra were observed for the first time under one/two-photon excitation. This phenomenon was attributed to thermal effects overcoming the biexciton binding energy. This study provides valuable insights for further optimizing multiexciton gain characteristics in SQWs and developing optical gain applications. [ABSTRACT FROM AUTHOR]

The critical role of specifying micro‐Doppler mode performance in the modelling and development of modern radar systems is investigated. The authors focus on the detection of micro‐Doppler modulation from light aircraft, analysing data from eight helicopters and nine propeller aircraft. With the growing need for accurate target classification in radar technology, incorporating micro‐Doppler detection metrics into radar performance specifications has become increasingly important. This research offers a novel approach to measuring the detectability of micro‐Doppler modulation relative to returns from the main fuselage. The investigation covers the impacts of various preprocessing techniques, polarisation, and aspect angle on detection capabilities. Findings reveal that, on average, micro‐Doppler modulation from propellers is detectable at distances between 50% and 100% of the range at which the fuselage is detected. For helicopters, this range decreases to between 30% and 80%. Additionally, the study introduces empirically derived statistical models designed to predict micro‐Doppler detection ranges in relation to fuselage returns, enhancing the predictability and specificity of radar system performance. This novel contribution presents a basis for improving radar system specifications, leading ultimately to more predictable and reliable light aircraft classification. [ABSTRACT FROM AUTHOR]

Highly efficient and programmable writing of multidimensional optical data is of great value for next‐generation high‐throughput information technologies but has been rarely achieved. Here, a one‐step frame printing of chromatic pixels in lithium niobate crystal by using a single ultrafast laser pulse is reported. In this strategy, a phase superposition‐based spatial light modulation strategy is applied to split a single ultrafast laser pulse into multiple son pulses with designated optical properties and spatial distribution patterns. It is demonstrated that these son pulses allow for massively creating micro‐amorphous phase transition zones with on‐demand structural features that can modulate the intrinsic birefringence of the crystal matrix and generate wavelength‐selective interference in the visible band to form pixel‐level chromatic patterns, namely, single‐pulse‐driven frame color printing. The created chromatic pixels can be encoded into computer‐recognizable data arrays to play a role in high‐efficiency multidimensional information recording. The presented approach enables fast and programmable information batch writing in 3D space and can serve as a versatile tool boosting next‐generation information optics. [ABSTRACT FROM AUTHOR]

The control of light through all‐optical means is a fundamental challenge in nanophotonics and a key effect in optical switching and logic. The optical bistability effect enables this control and can be observed in various planar photonic systems such as microdisk and photonic crystal cavities and waveguides. However, the recent advancements in flat optics with wavelength‐thin optical elements require nonlinear elements based on metastructures and metasurfaces. The performance of these systems can be enhanced with high‐Q bound states in the continuum (BIC), which leads to intense harmonic generation, improved light‐matter coupling, and pushes forward sensing limits. This study reports enhanced thermo‐optical nonlinearity and the observation of optical bistability in an all‐dielectric metasurface membrane with BIC. Unlike many other nanophotonic platforms, metasurfaces allow for fine control of the quality factor of the BIC resonance by managing the radiative losses. This provides an opportunity to control the parameters of the observed hysteresis loop and even switch from bistability to optical discrimination by varying the angle of incidence. Additionally, this work proposes a mechanism of nonlinear critical coupling that establishes the conditions for maximal hysteresis width and minimal switching power, which has not been reported before. The study suggests that all‐dielectric metasurfaces supporting BICs can serve as a flat‐optics platform for optical switching and modulation based on strong thermo‐optical nonlinearity. [ABSTRACT FROM AUTHOR]

Metasurfaces, which are ultrathin planar metamaterials arranged in certain global sequences, interact uniquely with the surrounding light field and exhibit unusual effects of light modulation. Many interesting applications have been discovered based on metasurfaces, particularly in invisibility cloaks. However, most invisibility cloaks are limited to working in specific directions. Achieving effectiveness in multiple directions requires the metasurface to be designed with both perception and modulation capabilities. Current multi-directional metasurface cloak systems are implemented with discrete components rather than an integrated sensing component. Here, we propose an intelligent metasurface cloak system that integrates sensing units, resulting in the cloaking effect with the help of a real-time direction sensor and an adaptive feedback control system. A reconfigurable reflective meta-atom based on phase modulation is presented. Sensing units replace parts of the meta-atoms in the designed tunable metasurface, integrating with an FPGA responsible for measuring the direction and frequency of the incident wave, constituting a closed-loop system together with the feedback parts. Experimental results demonstrate that the metasurface cloak system can recognize the different directions of the incoming wave, and can adaptively manipulate the reflected phase of EM waves to conceal objects without any human participation. [ABSTRACT FROM AUTHOR]

Purpose: Organ motion can significantly affect the accurate delivery of radiation doses to the tumor, particularly for sites such as the breast, lung, abdomen, and pelvis. Managing this motion during treatment is crucial. One strategy employed to manage motion induced from respiration is breath-hold (BH), which enhances the geometric precision of dose delivery. Our institute is transitioning to using the ExacTrac Dynamic system to facilitate patient BH using surface-guided cameras. Only 20% of our linacs are equipped with surface guidance capabilities, and due to a high patient stereotactic throughput, the ability to perform in-bunker coaching for BH patients within the bunker is limited. To address this challenge, a time-of-flight camera (ToF) was developed to coach radiotherapy patients undergoing BH procedures, allowing them to gain confidence in the process outside of the bunker and before treatment. Methods: The camera underwent testing for absolute and relative accuracy, responsiveness under various environmental conditions, and comparison with the Elekta Active Breathing Coordinator (ABC) to establish correlation and testing on volunteers independently to assess usability. Results: The results showed that the absolute distance measured by the camera was nonlinear due to square light modulation, which was retrospectively corrected. Relative accuracy was tested with a QUASAR motion phantom, with results agreeing to within ± 2 mm. The camera response was found to be unaffected by changes in lighting or temperature, though it overresponded under extreme temperatures. The comparison with the Elekta ABC system yielded comparable results between lung volume and changes in surface distance during BH. All volunteers successfully followed instructions and maintained BH within ± 1 mm tolerance. Conclusions: This study demonstrates the feasibility of using a cost-effective ToF camera to coach patients before imaging/treatment, saving valuable LINAC linac and imaging system time. [ABSTRACT FROM AUTHOR]

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Electrochromic materials enable the precise control of their optical properties, making them essential for energy-saving applications such as smart windows. This study focuses on the synthesis of molybdenum-doped niobium oxide (Mo-Nb2O5) thin films using a one-step hydrothermal method to investigate the effect of Mo doping on the material's electrochromic performance. Mo incorporation led to distinct morphological changes and a transition from a compact granular structure to an anisotropic rod-like feature. Notably, the MN-3 (0.3% Mo) sample displayed an optimal electrochromic performance, achieving 77% optical modulation at 600 nm, a near-perfect reversibility of 99%, and a high coloration efficiency of 89 cm2/C. Additionally, MN-3 exhibited excellent cycling stability, with only 0.8% degradation over 5000 s. The MN-3 device also displayed impressive control over color switching, underscoring its potential for practical applications. These results highlight the significant impact of Mo doping on improving the structural and electrochromic properties of Nb2O5 thin films, offering improved ion intercalation and charge transport. This study underscores the potential of Mo-Nb2O5 for practical applications in energy-efficient technologies. [ABSTRACT FROM AUTHOR]

As a basic building block, the THz wave absorber has intense imaging, sensing, and nondestructive testing applications. There are several methods for tuning THz absorbers, including electricity modulation, light modulation, mechanical tuning, using phase change materials, liquid crystal, flexible materials, MEMS technology, and thermally tuning vanadium dioxide. The choice of tuning method depends on the specific application and the desired performance characteristics of the THz absorber. In this work, we report a theoretical description of mechanically tunable THz absorber based on overlapping periodic arrays of graphene nano‐disks. The basis of this work is based on the movement of a dielectric surface covered on both sides with graphene disks. This surface moves on a fixed plane while the distance between these two surfaces is free space. Also, the fixed surface consists of a relatively thick layer of gold at the bottom, dielectric on it, and graphene disk patterns on the dielectric. Now, by moving the movable surface in the horizontal direction, it is possible to adjust the amount of absorption in different frequencies of the terahertz (THz) band. Additionally, an equivalent RLC circuit model is developed and theoretical results match with simulated data. The proposed mechanically tunable THz absorber can be exploited in various emerging applications such as sensing due to its capability of covering all of the THz gap and beyond with multiple absorption peaks. [ABSTRACT FROM AUTHOR]

The goal of this study is to develop a wireless-controlled robotic hand that is capable of replicating the movements of a human hand. A central objective of the design process is the development of a sensing technique that can accurately capture and translate human hand movements into electrical signals in a sustainable manner. This sensing technology relies on the detection of flexion and extension in the human hand, achieved through the modulation of light transmitted from a Light-Emitting Diode (LED) and received by a Light-Dependent Resistor (LDR). Five sensors, each corresponding to a finger, are integrated into a glove worn by the user, thereby enabling an intuitive control of the robotic hand. The sensors generate discrete electrical signals with each finger movement, which are then wirelessly transmitted via nRF24l01 modules to the microcontroller of the robotic hand. Subsequently, the microcontroller generates the requisite electrical signals to actuate the servo motors, thereby orchestrating the movement of the robotic fingers to mimic human hand gestures. The robotic hand, comprising 46 individual components fabricated using biodegradable polylactic acid material via 3D printing, successfully achieves its objective of replicating human hand movements. However, a minor delay in milliseconds is observed between human hand movements and the corresponding robotic hand movements. Despite this delay, the developed system shows promise for applications in hazardous environments, such as dangerous chemistry experiments, and enhances safety in the medical laboratory. It may also play a crucial role in remote surgery procedures. [ABSTRACT FROM AUTHOR]

Prussian blue (PB), as a promising inorganic electrochromic material (ECM), has been widely used in smart windows, displays, sensors, etc. However, there are still many challenges for PB to achieve high electrochromic performance. Herein, we synthesized nitrogen-doped carbon dots-modified PB film (defined as PB@N-CDs) with a sandwich-like structure by a simple stepwise electrodeposition method. The carbon dots show an obvious advantage in ultrafast electron transfer ability, which can reduce charge loss during the transfer process, improve the electrochemical activity on both sides of PB, and thus facilitate a rapid electrochromic response. Furthermore, the surface of nitrogen-doped carbon dots contains multiple organic functional groups, which widen the movement path of K+ ions under electrostatic adsorption. Impressively, the PB@N-CDs film exhibits a short bleaching/coloring time (0.5/0.9 s) and a superior optical modulation range (78.6%). Particularly, the coloring efficiency has been significantly improved to 137.71 cm2/C (at 700 nm). All of these results open up new avenues for developing high-performance PB-based ECMs and promoting their applications in corresponding electrochromic devices (ECDs) and smart windows. [ABSTRACT FROM AUTHOR]

The integrable substrate for THz modulation directly influences both the quality of films and THz absorption. Currently, the available THz substrate candidate library is still not clear. Here, we have carried out a systematic investigation of commonly used commercial substrates, including Si, quartz SiO2, MgO, Al2O3, GdScO3 and TbScO3 in the range of 0.4–1.6 THz. It is found that low resistance Si, TSO and GSO are certainly not appropriate for THz light modulation due to their relatively higher absorption and dielectric constant, while the rest show better THz transmittance, low refractive index and loss. However, the dielectric constant and refractive index of high resistance Si are generally two times larger than quartz SiO2, Al2O3 and MgO. Compared with Al2O3 and MgO, quartz SiO2 shows at least 50% lower dielectric constant, refractive index and absorption, making it the best candidate. Our research is believed to build the rich substrate candidate library for THz range light modulation. [ABSTRACT FROM AUTHOR]

A coherent optical receiver digital signal processing (DSP) scheme is proposed based on spectral clustering, which utilises spectral clustering to cluster the signals outputted by the DSP. Compared to existing blind DSP algorithms for coherent optical receivers operating at over 100Gbps with PM‐mQAM, the proposed scheme effectively suppresses various physical impairments, achieving lower bit error rates (BERs) at the same transmission distance, thus enabling longer transmission distances under the same forward error correction threshold. Furthermore, simulations of the proposed scheme on a 14GBaud PM‐16QAM coherent optical transmission system show that, at a BER of 1.9E‐2, the maximum transmission distance increases from 1700 to 2000 km, and at a BER of 3.8E‐3, it increases from 700 to 900 km. [ABSTRACT FROM AUTHOR]

This study examines the physical-layer security of an indoor visible light communication (VLC) system using spatial modulation (SM), which consists of several transmitters, an authorized receiver, and a passive adversary. The SM technique is applied at the transmitters so that only one transmitter is operational at any given time. A uniform selection (US) strategy is employed to choose the active transmitter. The two scenarios under examination encompass the conditions of non-negativity and average optical intensity, as well as the conditions of non-negativity, average optical intensity, and peak optical intensity. The secrecy rate is then obtained for these two scenarios while accounting for both signal-independent noise and signal-dependent noise. Additionally, the high signal-to-noise ratio (SNR) asymptotic behavior of the derived secrecy rate constraints is investigated. A channel-adaptive selection (CAS) strategy and a greedy selection (GS) scheme are utilized to select the active transmitter, aiming to enhance the secrecy performance. The current numerical findings affirm a pronounced convergence between the lower and upper bounds characterizing the secrecy rate. Notably, marginal asymptotic differentials in performance emerge at elevated SNRs. Furthermore, the GS system outperforms the CAS scheme and the US method, in that order. Additionally, the impact of friendly optical jamming on the secrecy rate is investigated. The results show that optical jamming significantly enhances the secrecy rate, particularly at higher power levels. [ABSTRACT FROM AUTHOR]

This paper presents the design of a strain-sensitive, dual ball-shaped tunable zone (DBT) taper structure for light intensity modulation. Unlike conventional tapered optical fibers, the DBT incorporates a central light field modulation zone within the taper. By precisely controlling the fusion parameters between single-mode fiber (SMF) and polarization-maintaining fiber (PMF), the ellipticity of the modulation zone can be finely adjusted, thereby optimizing spectral characteristics. Theoretical analysis based on polarization mode interference (PMI) coupling confirms that the DBT structure achieves a more uniform spectral response. In cantilever beam strain tests, the DBT exhibits high sensitivity and a highly linear intensity–strain response (R² = 0.99), with orthogonal linear polarization mode interference yielding sensitivities of 0.049 dB/με and 0.023 dB/με over the 0–244.33 με strain range. Leveraging the DBT's light intensity sensitivity, a temperature-compensated intensity difference and ratio calculation method is proposed, effectively minimizing the influence of light source fluctuations on sensor performance and enabling high-precision strain measurements with errors as low as ±6 με under minor temperature variations. The DBT fiber device, combined with this innovative demodulation technique, is particularly suitable for precision optical sensing applications. The DBT structure, combined with the novel demodulation method, is particularly well-suited for high-precision and stable measurements in industrial monitoring, aerospace, civil engineering, and precision instruments for micro-deformation sensing. [ABSTRACT FROM AUTHOR]

Dual‐band electrochromic smart windows (DESWs), capable of actively and selectively modulate visible (VIS) light and near‐infrared (NIR) heat, have emerged as a practical technology for enhancing user comfort and reducing building energy consumption. However, the design and development of DESWs remain a significant challenge due to the difficulty in obtaining suitable materials and high‐durability electrolytes. Here, the first all‐solid‐state DESW based on an orthorhombic oxygen‐deficient tungsten oxide (o‐WO3‐x) film is presented. Benefiting from the synergistic effects of the efficient oxygen‐vacancy‐enhanced charge transfer process and the secure transfer pathway enabled by the orthorhombic crystal structure, the o‐WO3‐x film showcases remarkable dual‐band electrochromic properties, including selective modulation of VIS light and NIR heat, large optical modulation (89.1%), rapid response time (tb/tc = 6.8/17.9 s), high coloration efficiency (155.92 cm2 C−1), and ultrastable cyclic performance (8000 cycles) even in acidic aqueous electrolyte. Furthermore, the all‐solid‐state DESWs incorporating o‐WO3‐x deliver a significant and stable dual‐band electrochromic response with excellent thermal regulation and energy‐saving capabilities. These findings underscore the considerable potential of o‐WO3‐x films and their all‐solid‐state smart windows in decreasing building energy consumption. [ABSTRACT FROM AUTHOR]

Multiple Fano resonances (mFRs) are arising as a promising optical platform to achieve precise sensing and detection. However, experimentally achieving mFRs by simple structures has remained challenging, which impedes the widespread applications of mFRs. Herein a simple structure composed of a single colloidal metal nanoparticle and a transition metal dichalcogenide flake to simultaneously achieve up to 8 FRs in experiments is demonstrated. Combining theoretical and experimental techniques, that an out‐of‐plane plasmon mode of the metal nanoparticle interferes with the Fabry–Pérot cavity modes from the WS2 flake to form mFRs in the visible region is proved. The simplicity and generality of the method further allow us to systematically study the tunability of the mFRs, in terms of the peak/dip positions and the number of FRs, by changing the structural parameters, which include the thickness of the WS2 flake, size and shape of the plasmonic nanoparticle. In addition, the quality of the mFRs is proved to be adjustable by tuning the reflectivity of the substrate in the system. The highest quality factor and spectral contrast of the achieved resonances are up to ≈180 and ≈0.95, respectively. The simple structure and high‐quality optical modes will prosper applications in precise sensing and light modulation. [ABSTRACT FROM AUTHOR]

A stimuli‐responsive multiple chirality switching material, which can regulate opposed chiral absorption characteristics, has great application value in the fields of optical modulation, information storage and encryption, etc. However, due to the rareness of effective functional systems and the complexity of material structures, developing this type of material remains an insurmountable challenge. Herein, a smart polymer film with multiple chirality inversion properties was fabricated efficiently based on a newly‐designed acid & base‐sensitive dye‐grafted helical polymer. Benefited from the cooperative effects of various weak interactions (hydrogen bonds, electrostatic interaction, etc.) under the aggregated state, this polymer film exhibited a promising acid & base‐driven multiple chirality inversion property containing record switchable chiral states (up to five while the solution showed three‐state switching) and good reversibility. The creative exploration of such a multiple chirality switching material can not only promote the application progress of current chiroptical regulation technology, but also provide a significant guidance for the design and synthesis of future smart chiroptical switching materials and devices. [ABSTRACT FROM AUTHOR]

The interface mismatch between electrochromic materials and conductive layer seriously affects the cycle stability of electrochromic smart windows (ESW). However, it is difficult to improve the interface matching at the same time because of the different physical and chemical properties of anode and cathode materials. In this work, SnO 2 nanosheets are used as the interface modification layer between electrochromic materials and conductive layer. SnO 2 interface engineering significantly can improve the cycle stability of WO 3 film and Prussian blue (PB) film. The WO 3 /SnO 2 -PB/SnO 2 complementary ESW exhibits a high optical modulation of 60.2 % at 633 nm, fast response time (bleached/colored time = 8.5/2.5 s), and coloration efficiency of 91.7 cm2 C−1. The WO 3 /SnO 2 -PB/SnO 2 device can still maintain an optical modulation of 45.2 % after 2000 cycles, suggesting excellent long cycle stability. And the device shows the energy storage of 5.06 mF cm−2 at 0.1 mA cm−2, which can improve energy efficiency. The excellent electrochromic properties and energy storage suggests that SnO 2 interface engineering has a good application prospect in multi-functional ESW with excellent cycle stability. [ABSTRACT FROM AUTHOR]

This study reports the fabrication of electrochromic Ag decorated V 2 O 5 thin film by thermal evaporation method at 10−5 torr vacuum medium and the effects of the Ag doping to the V 2 O 5 matrix. Besides, the electrochromic capabilities and energy-saving characteristics of the films are also in the scope of this study. Structural and morphological properties are investigated by XRD, FESEM, and AFM. The films have a polycrystalline structure and a porous surface. FTIR and Raman spectra verify the molecular formation of the films. The performance of the electrochromic films is characterized by a variety of techniques such as cyclic voltammetry, chronoamperometry, chronocolumetry, and electrochemical impedance spectroscopy. The color of the films changes from yellow to green and then from green to blue in the range of −1.2 and + 1.0 V vs Ag/AgCl with a reversibility of 92.9 %. With the response times of t b = 13.6 s and t c = 9.4 s, an optical modulation of 51.7 % (from yellow to blue), and a coloration efficiency of 93.7 cm2 C−1, Ag:V 2 O 5 becomes an impressive electrochromic material produced by physical methods. Linear sweep voltammetry studies show that the photocurrent of both V 2 O 5 /ITO and Ag:V 2 O 5 /ITO electrodes increases under solar illumination. The supercapacitive performance of the film is investigated by cyclic voltammetry, and Ag:V 2 O 5 is an encouraging electrode material with a specific capacitance of 720.9 F g−1 at 5 mV s−1 scan rate. An equivalent circuit is fitted from the film Nyquist data and the results also confirm the positive contribution of Ag doping on the response times, energy saving, and photoresponse of V 2 O 5 thin film. In this regard, the produced electrodes are highly promising for potential applications in electrochromic, energy storage, and photovoltaic devices. [ABSTRACT FROM AUTHOR]

Flexible organic crystalline optical waveguides, which deliver input or self‐emit light through various dynamic organic crystals, have attracted increasing attention in the past decade. However, the modulation of the waveguide output relies on chemical design and substituent modification, being time‐consuming and laborious. Here we report an elastic organic crystal that displays long‐distance light transduction up to 2.0 cm and an ultra‐wide modulation of crystalline optical waveguides between red (645 nm) and near infrared (731 nm) in both the pristine and the elastically bent states based on a pre‐designed self‐absorption effect. The flexible organic crystalline optical waveguides can be precisely and reversibly reconfigured by controlling the irradiation point. In addition, deep‐red amplified spontaneous emission (ASE) that is able to transduce through a 5.0 mm bent crystal with an ultra‐low optical loss coefficient of 0.093 dB/mm has been attained. To the best of our knowledge, this is the first report of flexible organic ASE waveguides. The present study not only provides a simple yet effective strategy to remarkably modulate flexible organic crystalline optical waveguides but also demonstrates the superiority of lasing over normal emission as flexible optical communication elements. [ABSTRACT FROM AUTHOR]

Low‐dimensional lead halide perovskites demonstrate remarkable nonlinear optical characteristics attributed to their distinctive physical structures and electronic properties. Nevertheless, the investigation into their nonlinear optical properties remains in its incipient stages. This study addresses this gap by precisely controlling solvent volumes to synthesize both 0D Cs4PbBr6 and Cs4PbBr6/CsPbBr3 perovskites. Remarkably, as saturable absorbers, both pure Cs4PbBr6 and Cs4PbBr6/CsPbBr3 composites exhibit favorable nonlinear optical properties within the C‐band, showcasing modulation depths of 9.22% and 16.83%, respectively. Moreover, for the first time, Cs4PbBr6 and Cs4PbBr6/CsPbBr3 composites have been successfully integrated into erbium‐doped fiber lasers to realize the mode‐locking operations. The utilization of the Cs4PbBr6/CsPbBr3 composites as a saturable absorber that enables the generation of conventional soliton mode‐locked laser pulses with a pulse duration of 688 fs, and a repetition frequency of 10.947 MHz at a central wavelength of 1557 nm. Cs4PbBr6 is instrumental in generating laser pulses at a frequency of 10.899 MHz, producing pulse widths of 642 fs at the central wavelength of 1531.2 nm and 1.02 ps at the central wavelength of 1565.3 nm, respectively. The findings of this investigation underscore the potential utility of 0D Cs4PbBr6 and Cs4PbBr6/CsPbBr3 composites as promising materials for optical modulation within fiber laser applications. [ABSTRACT FROM AUTHOR]

Optical microcavities, particularly whispering gallery mode (WGM) microcavities enhanced by plasmonic nanorods, are emerging as powerful platforms for single‐molecule sensing. However, the impact of optical forces from the plasmonic near field on analyte molecules is inadequately understood. Using a standard optoplasmonic WGM single‐molecule sensor to monitor two enzymes, both of which undergo an open‐to‐closed‐to‐open conformational transition, the work done on an enzyme by the WGM sensor as atoms of the enzyme move through the electric field gradient of the plasmonic hotspot during conformational change has been quantified. As the work done by the sensor on analyte enzymes can be modulated by varying WGM intensity, the WGM microcavity system can be used to apply free energy penalties to regulate enzyme activity at the single‐molecule level. The findings advance the understanding of optical forces in WGM single‐molecule sensing, potentially leading to the capability to precisely manipulate enzyme activity at the single‐molecule level through tailored optical modulation. [ABSTRACT FROM AUTHOR]

We present a hollow cylindrical three-dimensional nonlinear photonic crystal for annular beam shaping. By inducing a modification with the near-infrared femtosecond laser inside lithium niobate, we experimentally achieve second-order nonlinear optical coefficient modulation in three dimensions. The center dark spot ratio of the generated annular beam can be adjusted by varying the hollow ratio of the cylindrical structure. To demonstrate the controlled linear variation of the annular distribution, we generate annular beams with center dark spot ratios ranging from 0 to 0.7. Furthermore, we illustrate the feasibility of the generated annular beam in optical trapping by manipulating glass powder particles with diameters of 4–10 μm in water. Our hollow cylindrical structure owns effective control of beam dark spot ratio, while providing a tool for generating annular beam. [ABSTRACT FROM AUTHOR]

To locate and fertilize the egg, sperm probe the varying microenvironment prevailing at different stages during their journey across the female genital tract. To this end, they are equipped with a unique repertoire of mostly sperm-specific proteins. In particular, the flagellar Ca2+ channel CatSper has come into focus as a polymodal sensor used by human sperm to register ligands released into the female genital tract. Here, we provide the first comprehensive study on the pharmacology of the sperm-specific human Slo3 channel, shedding light on its modulation by reproductive fluids and their constituents. Weshow that seminal fluid and contained prostaglandins and Zn2+ do not affect the channel, whereas human Slo3 is inhibited in a non-genomic fashion by diverse steroids as well as by albumin, which are released into the oviduct along with the egg. This indicates that not only CatSper but also Slo3 harbours promiscuous ligandbinding sites that can accommodate structurally diverse molecules, suggesting that Slo3 is involved in chemosensory signalling in human sperm. [ABSTRACT FROM AUTHOR]

Hydrogel smart windows with light modulation capability have received widespread attention because they can meet the requirements of indoor lighting at daytime, privacy protection at night and energy saving. However, it remains challenging to achieve these multiple goals simultaneously and enable active actuation to meet the temporary needs of users. In this study, a thermal and solvent responsive hydrogel smart window was developed by introducing hydroxypropyl cellulose (HPC) and sodium dodecyl sulfate (SDS) micelles into a polyacrylamide (PAAm) cross-linked network. By adding different concentrations of NaCl solution, the hydrogels underwent upper critical solution temperature (UCST)- and lower critical solution temperature (LCST)-type phase transitions in the ranges of 1 − 15 °C and 25 − 80 °C, respectively, which enabled the hydrogel to achieve a reversible transition between opacity and transparency with temperature change. The smart window exhibited an excellent solar modulation ability (Tlum = 91.39%, ΔTsol,15−5℃ = 68.67%, ΔTsol,15−40℃ = 62.50%) and effective IR shielding. Furthermore, actively actuated light modulation of hydrogel smart windows was achieved by spraying ethanol on the hydrogel surface. Ethanol stimulation and volatilization induced the reconfiguration and dissociation of hydrogen bonds between HPC and PAAm molecular chains, resulting in reversible transparency transitions. We anticipate that this facile strategy for preparing thermal and solvent responsive hydrogels could serve as a promising alternative for designing phase change hydrogels for a variety of applications. [ABSTRACT FROM AUTHOR]

Phase change materials (PCM) have greatly contributed to optics with applications ranging from rewritable memories to smart windows. This is possible thanks to the variation in optical properties that PCMs undergo upon thermally‐induced phase change. However, this behavior is accompanied by a loss of optical transparency in one (or more) of their phases, posing a major limitation for transmission‐based functionalities. Here this challenge is addressed by producing PCM‐based composites that remain transparent in the visible spectrum during their phase transition. The cornerstone of this innovative material is the use of 30 nm‐in‐size nanoparticles of paraffin as PCMs, which minimizes the scattering within the polymer host matrix regardless of the paraffin's phase. To demonstrate the potential of this approach, it is shown that thin composite layers can modulate the phase of the incident visible light using temperature, achieving uniform phase profiles with maximum phase shifts up to π radians. Notably, the composites studied exhibit up to threefold larger phase changes for the same input power over reference thermo‐optical materials like polydimethylsiloxane. These findings position paraffin‐based composites as promising materials for various thermo‐optical applications, including wavefront shaping and aberration correction, with the potential to significantly impact a variety of optical technologies. [ABSTRACT FROM AUTHOR]

Nanoscale optical sensing plays a crucial role in achieving high‐precision non‐contact distance and displacement measurements. As one of the promising alternatives, structured light can greatly simplify optical sensing systems. In this study, a novel optical phenomenon of a structured beam called the "Dumpling‐shaped Structured Light Field" (DSLF) is revealed, which forms during the focusing of cylindrical lens beams. The 3D DSLF comprises two mutually perpendicular primary and secondary foci, offering unique possibilities in micro/nano processing and sensing applications. A thorough investigation of the DSLF is conducted, revealing a correlation between the secondary foci and the phase status at the objective lens's entrance pupil. The propagation of DSLF under tight focus conditions has been verified and discussed through methods of femtosecond laser two‐photon polymerization and light field analysis. Finally, thanks to the unique 3D intensity distribution of 3D DSLF, the applicability of DSLF in high‐precision position and vibration sensing has been demonstrated. By detecting the horizontal and vertical dimensions of the reflected DSLF, position and vibration sensing is achieved with a Z‐direction accuracy of 10 nm (λ/80). This research contributes to understanding structured light, and offers practical applications in various fields, including micro/nano laser processing, optical imaging, sensing, etc. [ABSTRACT FROM AUTHOR]

Thermochromic perovskite materials exhibit reversible color changes in response to external thermal stimuli. Recently recognized as promising candidates, significant efforts are dedicated to developing these materials with tunable properties, rapid response, and effective light modulation. This review demonstrates recent advances in fabrication methods, mechanism investigation, solar modulation performance, and diverse applications of perovskite thermochromic materials. Thin films and single crystals are addressed separately, with a focus on achieving high‐quality and stable thermochromic perovskite materials across different dimensional architectures. Furthermore, the article outlines current challenges and provides forward‐looking perspectives, aiming to foster future innovative research and widespread application in smart windows, switchable photovoltaic devices, photo/thermal detectors, and anti‐counterfeiting technologies. [ABSTRACT FROM AUTHOR]

In this study, we propose and simulate a magnetoplasmonics heterostructure that utilizes spin–orbit fields to generate an internal magnetic field and create a significant magneto-optical effect. Our approach offers a new way to overcome the challenges of using permanent magnets or magnetic coils in conventional magnetoplasmonics, such as high-power consumption and non-scalability. We demonstrate that it is possible to create an appropriate amount of magnetic field using spin–orbit fields induced by the spin-Hall effect, such that the consumption power becomes reasonable and the dimensions could be miniaturized. This approach will be an important development in the field of magneto-optics, as it can lead to enhanced transverse magneto-optical Kerr effect in the present of surface plasmon polaritons. The proposed nanostructure consists of a ferromagnetic film adjacent to a heavy metal layer, both sandwiched between two noble metal films, and deposited on a dielectric prism. The strength of the Kerr signal strongly depends on the thickness of the ferromagnetic layer, with the maximum effect observed at a thickness of 5nm. This concept has potential for various nanophotonic and spintronic applications, particularly for developing high-speed active plasmonic devices for ultrafast light modulation. [ABSTRACT FROM AUTHOR]

Hydrazine, a compound known for its toxicity to human health and the environment, finds extensive use across various industries and potentially contributes to several diseases. Hence, the accurate measurement of hydrazine levels is paramount. This study introduces three new aggregation induced emissive luminogens (AIEgens) GBY-7, GBY-8, and GBY-9 crafted from benzofuran infused with a dicyanovinylidene group, tailored specifically for hydrazine monitoring. These probes feature a D–π–A core with a rotor, providing an optimal fluorescent base. Additionally, a potent electron-attracting nitrile group aids in the nucleophilic addition of N2H4 to form hydrazone, thereby blocking the intramolecular charge transfer (ICT) process and inducing optical signal modulation. Notably, luminogens GBY-8 and GBY-9 exhibit high selectivity in detecting hydrazine amidst competing amine-based compounds, showing detection limits of 0.00020 mM and 0.0043 mM, respectively. [ABSTRACT FROM AUTHOR]

Constructing self‐adaptive oscillators that can continuously, stably, and tunably transform external stimulus into mechanical work is high demand for soft robots, energy harvesters and object conveyors. However, these systems are challenging to develop because of the single mesogenic anisotropy and simple material constituents obtained by a traditional technique. Here, a photoactivated self‐adaptive liquid crystal elastomer (LCE) oscillator with controlled nanoassembly‐directed hierarchically anisotropic structure is demonstrated by developing the highly‐aligned silver nanowire (AgNW) assemblies (HAs) to guide the orientation and polymerization of LC molecules. The fabricated HAs‐LCE film exhibits tunable multiple anisotropies on mesogenic alignment, composition, density gradient across the thickness and mechanical behaviors. Combined with excellent photo‐driven bending deformation, the HAs‐LCE cantilever performs a self‐sustained, periodic and steady oscillation self‐propelled by negative feedback loops under a continuous NIR laser. Impressively, triggered by synergetic deformations of anisotropically responsive architecture, self‐adaptive oscillations are first achieved with self‐tunable frequencies spanning from 4.1 to 13.2 Hz to accommodate variable light intensity, showing enormous and distinctive potentials for optical modulation. [ABSTRACT FROM AUTHOR]

Neuromorphic devices are electronic devices that mimic the information processing methods of neurons and synapses, enabling them to perform multiple tasks simultaneously with low power consumption and exhibit learning ability. However, their large-scale production and efficient operation remain a challenge. Herein, we fabricated an aluminum-doped zinc oxide (AZO) synaptic transistor via solution-based spin-coating. The transistor is characterized by low production costs and high performance. It demonstrates high responsiveness under UV laser illumination. In addition, it exhibits effective synaptic behaviors under blue LED illumination, indicating high-efficiency operation. The paired-pulse facilitation (PPF) index measured from optical stimulus modulation was 179.6%, indicating strong synaptic connectivity and effective neural communication and processing. Furthermore, by modulating the blue LED light pulse frequency, an excitatory postsynaptic current gain of 4.3 was achieved, demonstrating efficient neuromorphic functionality. This study shows that AZO synaptic transistors are promising candidates for artificial synaptic devices. [ABSTRACT FROM AUTHOR]

In this study, we examine the modulation of light transmission via a one-dimensional polymeric symmetrical Fibonacci-multilayer. The multilayer is constructed using substitutional generalised Fibonacci using PMMA and PS as the constituent materials. The widely recognised transfer matrix approach is utilised to derive theoretical results. The results of our investigation indicate that the width, spacing, and depth of the PBG can be modified by choosing the proper generation number. Remarkably, the count of significant PBGs remains consistent throughout all generation numbers, with the exception of the 10 th generation symmetrical Fibonacci-multilayer, which exhibits a pronounced localization. As the generation number grows, a symmetrical shift of the PBGs is noticed in relation to their position. Moreover, it has been shown that the forbidden frequency range can be adjusted by changing the hydrostatic pressure applied. The rise in pressure causes a shift in the frequency spectrum towards higher frequencies. Furthermore, our findings indicate that augmenting the polymer thickness leads to a shift towards longer wavelengths, known as a redshift, in the PBGs. This paper presents a new method for creating optical devices, specifically multi-band tunable optical filters and durable optical sensors, using one-dimensional polymeric symmetrical Fibonacci multilayers. [ABSTRACT FROM AUTHOR]

Background and Purpose: Amyloid‐β (Aβ) peptide is one of the more important pathological markers in Alzheimer's disease (AD). The development of AD impairs autophagy, which results in an imbalanced clearance of Aβ. Our previous research demonstrated that AdipoRon, an agonist of adiponectin receptors, decreased the deposition of Aβ and enhanced cognitive function in AD. However, the exact mechanisms by which AdipoRon affects Aβ clearance remain unclear. Experimental Approach: We studied how AdipoRon affects autophagy in HT22 cells and APP/PS1 transgenic mice. We also investigated the signalling pathway involved and used pharmacological inhibitors to examine the role of autophagy in this process. Key Results: AdipoRon promotes Aβ clearance by activating neuronal autophagy in the APP/PS1 transgenic mice. Interestingly, we found that AdipoRon induces the nuclear translocation of GAPDH, where it interacts with the SIRT1/DBC1 complex. This interaction then leads to the release of DBC1 and the activation of SIRT1, which in turn activates autophagy. Importantly, we found that inhibiting either GAPDH or SIRT1 to suppress the activity of SIRT1 counteracts the elevated autophagy and decreased Aβ deposition caused by AdipoRon. This suggests that SIRT1 plays a critical role in the effect of AdipoRon on autophagic induction in AD. Conclusion and Implications: AdipoRon promotes the clearance of Aβ by enhancing autophagy through the AdipoR1/AMPK‐dependent nuclear translocation of GAPDH and subsequent activation of SIRT1. This novel molecular pathway sheds light on the modulation of autophagy in AD and may lead to the development of new therapeutic strategies targeting this pathway. [ABSTRACT FROM AUTHOR]

Polymer\liquid crystal composites have garnered significant attention as a material due to their facile preparation and pronounced light modulation effect. With the increasing range of applications, effectively modulating the relevant electro-optical parameters has emerged as a major challenge. In this study, two specific monomers were chosen to investigate the impact of curing conditions on the electro-optical parameters. Compared to previous research, the findings presented here offer a much simpler approach for regulating the parameters. This work not only provides insights for future advancements in polymer\liquid crystal composites with novel functionalities and morphologies but also serves a valuable reference for related industrial production. [ABSTRACT FROM AUTHOR]

Ferroelectric field effect transistors (Fe-FETs) offer promising candidates for neuromorphic computing. However, it is still challenging to achieve a light-tunable field effect, which limits the function of photo-synapse. In this work, a ferroelectric semiconductor floating-gate transistor (FSF-FET) is proposed based on MoS2/h-BN/α-In2Se3 van der Waals heterojunctions (vdWHs), in which the two-dimensional ferroelectric semiconducting α-In2Se3 and dielectric h-BN serve as the trapped layer of charges and prevent layer, respectively. The excellent memory performances are exhibited, including a high programming/erasing ratio of over 107, a large memory window ratio of 74.69%, and good non-volatility. Moreover, the FSF-FETs also possess the light-tunable synapse behaviors, including the high paired-pulse facilitation of 236% and an obvious transition from short-term plasticity to long-term plasticity. The high recognition rate of 93.9% is achieved with dual-mode modulation of light and electrical pulses. The ferroelectric semiconductor floating-gate design opens up a strategy to realize the light-tunable field effect of Fe-FETs for photo-synapse. [ABSTRACT FROM AUTHOR]

Phase‐based light detection and ranging (LiDAR) technology is emerging in the fields of industrial mapping, autonomous driving, and robotics, but the traditional phase‐based ranging technology generally suffers from the problem that the ranging accuracy is inversely proportional to the measurement range under a single measurement frequency, the system structure is complicated, and the performance is unstable, and so forth. In this article, a new type of LiDAR system design based on phase ranging is proposed. The system adopts a 100 + 1 MHz double measuring ruler modulation light source, uses the laser to control the phase difference detection method of the same frequency reference, optimizes the structure of the transceiver optical system, and the design of AD8302 high‐resolution signal phase discriminator circuit, builds a high‐precision laser ranging system, and carries out the experiments on the measurement accuracy of the LiDAR ranging system. The experimental results show that the measurement accuracy of the system is millimeter level, which is simple, practical, and can meet the needs of a wide range of practical applications. This study provides a feasible and innovative solution for LiDAR technology in high‐precision distance measurement. [ABSTRACT FROM AUTHOR]

The electrocatalytic conversion of CO2 to produce fuels and chemicals holds great promise, not only to provide an alternative to fossil feedstocks, but also to use renewable electricity to convert and recycle the greenhouse gas CO2 to mitigate climate problems. However, the selectivity and reaction rates for the conversion of CO2 into desirable carbon-based products, especially multicarbon products with high added value, are still insufficient for commercial applications, which is attributed to insufficiently favourable microenvironmental conditions in the vicinity of the catalyst. The construction of catalysts/electrodes with confined structures can effectively improve the reaction microenvironment in the vicinity of the electrodes and thus effectively direct the reaction towards the desired pathway. In this review, we firstly introduce the effects of the microenvironment at the electrode-electrolyte interface including local pH, local intermediate concentration, and local cation concentration on CO2 reduction reaction (CO2RR) as well as the mechanism of action, and then shed light on the microenvironmental modulation within the confined space, and finally and most importantly, introduce the design strategy of CO2RR catalyst/electrode based on the confinement effect. [ABSTRACT FROM AUTHOR]

Flavor is a major sensory attribute affecting consumers' preference for cheese products. Differences in cheesemaking change the cheese microenvironment, thereby affecting cheese flavor profiles. A framework for tuning cheese flavor is proposed in this study, which depicts the full picture of flavor development and modulation, from manufacturing and ripening factors through the main biochemical pathways to flavor compounds and flavor notes. Taking semi‐hard and hard cheeses as examples, this review describes how cheese flavor profiles are affected by milk type and applied treatment, fat and salt content, microbiota composition and microbial interactions, ripening time, temperature, and environmental humidity, together with packaging method and material. Moreover, these factors are linked to flavor profiles through their effects on proteolysis, the further catabolism of amino acids, and lipolysis. Acids, alcohols, ketones, esters, aldehydes, lactones, and sulfur compounds are key volatiles, which elicit fruity, sweet, rancid, green, creamy, pungent, alcoholic, nutty, fatty, and sweaty flavor notes, contributing to the overall flavor profiles. Additionally, this review demonstrates how data‐driven modeling techniques can link these influencing factors to resulting flavor profiles. This is done by providing a comprehensive review on the (i) identification of key factors and flavor compounds, (ii) discrimination of cheeses, and (iii) prediction of flavor notes. Overall, this review provides knowledge tools for cheese flavor modulation and sheds light on using data‐driven modeling techniques to aid cheese flavor analysis and flavor prediction. [ABSTRACT FROM AUTHOR]

In this study, a kind of in-fiber Mach–Zehnder interferometer (MZI) is designed and experimentally examined. The MZI is composed of two in-fiber S-shaped cores (SSCs), which enhance strain sensitivity. To prepare the SSCs, a high-frequency CO2 laser is first utilized to polish grooves on the symmetrical surface of a single-mode fiber (SMF). The polished area is then subjected to arc-discharging by a commercial fusion splicer, and the core of the fiber bends towards the polished grooves due to the self-roundness of the cladding and the heating effect of discharge. The results of the experiments demonstrate that the sensor achieves high strain sensitivities of −66.5 pm/με and −40.1 pm/με within the strain range of 0 με to 350 με. By solving the matrix equation, simultaneous online measurements of temperature and strain can be performed. With the advantages of easy fabrication, low cost, high sensitivity, and compactness, the proposed sensor is a competitive candidate in strain sensing. [ABSTRACT FROM AUTHOR]

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Static and dynamic characteristics of a quantum dot (QD) laser with double asymmetric barrier layers – an advanced type of semiconductor laser – are studied. Both direct and indirect capture of carriers into the lasing ground state in QDs is considered. The intradot relaxation of carriers, which controls the laser characteristics in the case of only indirect capture, is shown to not be a significant factor in the case of both direct and indirect capture. In the latter case, both the output optical power and modulation bandwidth are considerably increased. [ABSTRACT FROM AUTHOR]