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An ultra-sparse, broadband programmable Active Acoustic Meta-surface (AAMS) that is demonstrated to function as a multi-functional Active Acoustic Meta-device is developed. Functionalities Acoustic Barrier (AB), Acoustic Switch (AS), and Acoustic Transmitter (AT) have been successfully explored. AB functions at a broadband frequency of 455 to 679 Hz as an approximately 100 % acoustic reflector. The functional range of the AS is 425 to 800 Hz, and similarly, the functional range of the AT is 300 to 800 Hz (the full range of the applied frequency sweep). Being a re-configurable device, the AAMS has variable thickness. On a wavelength scale, it varies from 0.10 λ to 0.99 λ for the said functionalities. Here, λ is the wavelength. [ABSTRACT FROM AUTHOR]

Despite rather extensive study of the random lasing effect in ZnO structures, the issue of the optical gain mechanisms in microstructured ZnO random lasers remains poorly understood. In this work, the radiative properties of an array of vertically aligned ZnO microrods, synthesized by a modified thermal evaporation method, were studied. The microrods exhibited lengths up to 60 μm and diameters ranging from 1 to 5 μm. Random lasing from a microrod array was observed in the near-UV range (with a laser emission peak wavelength of ∼391 nm) with a threshold down to 40 kW/cm2 under optical excitation. An analysis of the nature of optical gain in the grown structure was conducted at various temperatures. It was found that at room temperature, two-phonon-assisted exciton recombination is the main process leading to light amplification. [ABSTRACT FROM AUTHOR]

The double-ion chamber (DIC) method has been used to measure photoabsorption cross sections in the ionization region of the sample gas. In this study, we introduce a method to extend the wavelength region of the DIC measurements beyond the ionization threshold wavelength by using the photoion currents from the impurities in the sample gas. To verify this method, the photoabsorption cross sections of C2H2 (ionization threshold wavelength λth = 108.8 nm) have been measured from 105 to 137 nm. The natural impurity, acetone (λth = 127.8 nm), contained 1% in high-purity grade acetylene (C2H2) sample gas, allowing for measurements in the non-ionizing region of C2H2 up to 127.7 nm. By adding 1% benzene (λth = 134.6 nm) in the sample gas, measurements were possible even further, to 134.5 nm. This new method enables the measurement of the photoabsorption cross section by photoions that are produced from the impurities in the sample gas in a substantial amount. The current measurement methodology aligns well with the previous measurements of Suto and Lee [Suto and Lee, J. Chem. Phys. 80, 4824 (1984)]. [ABSTRACT FROM AUTHOR]

Asymmetric quantum wells (AQWs) utilizing interband transitions enhance second-order susceptibility over a wide wavelength range compared to natural crystals. The nonlinear susceptibility is further enhanced in AQWs with type-II band alignment as compared to type-I band alignment, a result of the larger interband charge shift. This enhancement is demonstrated in this work by analyzing three type-I and type-II AQW designs based on the lattice-matched InP/AlGaInAs materials systems using the envelope wavefunction approximation. The calculated interband second-order susceptibility tensor elements in type-II structures range between 20 and 1.60 × 103 pm/V for nearly resonant optical rectification and difference frequency generation applications at near-infrared and terahertz wavelengths, an improvement of nearly 1 order of magnitude over the type-I structures and 1–2 orders of magnitude over natural crystals such as LiNbO3, KTiOPO4 (KTP), or GaAs. A factor of 2–3 further enhancement of the tensor elements is achieved by optimizing the well widths and band offsets of the type-II asymmetric quantum wells. The type-II structure can be implemented in other material systems spanning the longwave infrared to visible wavelengths, enhancing nonlinear susceptibility for various applications, including photonic integrated circuits. [ABSTRACT FROM AUTHOR]

Magic-sized nanocrystals (MSNCs) grow via jumps between very specific sizes. This discrete growth is a possible avenue toward monodisperse nanomaterials that are completely identical in size and shape. In spite of this potential, MSNCs have seen limited study and application due to their poor optical properties. Specifically, MSNCs are limited in their range of emission wavelengths and commonly exhibit poor photoluminescence quantum yields (PLQYs). Here, we report silver doping of CdSe MSNCs as a strategy to improve the optical properties of MSNCs. Silver doping leads to controllable shifts in emission wavelength and significant increases in MSNC PLQYs. These results suggest that doped MSNCs are interesting candidates for displays or luminescent solar concentrators. Finally, we demonstrate that the doping process does not affect the magic size of our MSNCs, allowing further photophysical study of this class of nanomaterial. [ABSTRACT FROM AUTHOR]

Indium tin oxide (ITO) film, which is the most commonly used transparent conductive film (TCF), has traditionally been believed to be transparent in the visible spectrum but to reflect infrared (IR) light beyond the plasma wavelength (λp). However, our theoretical analysis challenges this notion by demonstrating that an ultrathin ITO TCF that is thinner than the light's penetration depth can overcome the transmission barrier at λp. To validate the theoretical modeling, we have successfully fabricated ultrathin ITO films that, despite having λp ≈ 1 μm, remain transparent from 400 nm to 20 μm. This represents the broadest transparency range ever reported for any In2O3-based TCF. The 10-nm-thick ITO TCFs have high visible transmittance (91.0% at 550 nm), low resistivity (5 × 10−4 Ω cm), and good IR transmittance (averaging 60% over 1.35–18.35 μm). Their IR transparency facilitates radiative cooling of the underlying circuitry. When an operational resistor is enclosed by commercial ITO TCFs that are 140 nm thick, its temperature increases. However, using 10-nm-thick ITO TCFs instead of the commercial ones can completely avoid this temperature rise. Moreover, attaching a silver grid to a 10-nm-thick ITO TCF can reduce the effective sheet resistance to ∼10 Ω/□ at the expense of only ∼3% transmittance. This development paves the way for large-scale applications that require low sheet resistance and far-IR transparency. [ABSTRACT FROM AUTHOR]

Faraday polarization rotation control of 1529 nm wavelength has been obtained using the 5 S 1 / 2 → 5 P 3 / 2 → 4 D 5 / 2 transition of rubidium. The traditional off-resonant polarization rotation method commonly used in the Faraday effect for direct transitions of atoms is not applicable to the transitions between excited states. In this study, we proposed a near-resonant polarization rotation method using the Faraday effect between excited states of atoms, by which the polarization rotation of the rubidium 5 P 3 / 2 → 4 D 5 / 2 transition can be controlled from 0 ° to 90 ° with low distortion. The 780 nm pump light corresponding to the 5 S 1 / 2 → 5 P 3 / 2 transition can also be used simultaneously as a control source to manipulate the polarization state of the 1529 nm optical signal. [ABSTRACT FROM AUTHOR]

The blue-violet emitting phosphors is a critical aspect of achieving a high-quality full-spectrum white light-emitting diodes (WLEDs). Here, the photoluminescence characteristics of blue-violet emitting phosphors Li 6 Y(BO 3) 3 :Bi3+ and its application performances were systematically studied. The emission of the phosphors exhibits a high dependence on the excitation wavelength. Upon excitation at 372 nm, the phosphors emit blue light peaking at 407 nm. The excitation of 340 nm results in the occurrence of two peaks at 407 and 506 nm in emission spectra. A full-spectrum WLED prepared by coating a 365 nm n-UV LED and the mixture comprising the phosphors and three commercial phosphors. The WLED exhibits high color rendering index (R a = 95) and low correlated color temperature (3555 K). Consequently, Li 6 Y(BO 3) 3 :Bi3+ is a potential phosphor that can be used for full spectrum WLEDs. [ABSTRACT FROM AUTHOR]

We describe the use of acyl imidazoles derived from aliphatic carboxylic acids for the N-heterocyclic carbene/organic photoredox co-catalyzed meta -selective functionalization of electron-rich arenes. Compared to our previous work, a change of the wavelength of the applied LED light from 440 nm to 390 nm promotes this reaction efficiently. [ABSTRACT FROM AUTHOR]

Different track failures are proven to have different influences on train-track interactions, but their influence on pantograph-catenary interactions has not been investigated thus far. In this work, the influences of typical track failures on pantograph-catenary interaction dynamics are first investigated. A reduced train-track-pantograph-catenary interaction model is developed to study these effects. In this model, the long catenary is reduced to a small moving area around the moving pantograph, and this area is considered and modelled as the reduced catenary model based on the arbitrary Lagrangian–Eulerian method. The reduced catenary model and moving pantograph are formulated as the reduced pantograph-catenary interaction model, and it is further unidirectionally connected with the existing reduced train-track interaction model to formulate the reduced train-track-pantograph-catenary interaction model. The present reduced pantograph-catenary model is first validated by the EN50318-2018 standard, and the influences of track irregularity, track buckling, fastening failure, and track settlement on pantograph-catenary interaction dynamics are studied. The investigation results first show that the track settlement with a long wavelength has a significant influence on the pantograph-catenary interaction dynamics and can even cause contact loss with a good train-track interaction behaviour. Thus, it should be further mentioned in the maintenance of the track structure. [ABSTRACT FROM AUTHOR]

We present exponential wave integrator Fourier pseudospectral (EWI‐FP) methods and establish their error estimates of the fully discrete schemes for the Dirac equation in the massless and nonrelativistic regime. This regime involves a small dimensionless parameter where 0<ε≤1$$ 0<\varepsilon \le 1 $$, and ε$$ \varepsilon $$ is inversely proportional to the speed of light. The solution exhibits highly oscillatory behavior in time and rapid wave propagation in space in this regime. Specifically, the time oscillations have a wavelength of O(ε)$$ O\left(\varepsilon \right) $$, while the spatial oscillations have a wavelength of O(1)$$ O(1) $$, with a wave speed of O(ε−1)$$ O\left({\varepsilon}^{-1}\right) $$. We employ (symmetric) exponential wave integrators for temporal derivatives and Fourier spectral discretization for spatial derivatives. We rigorously derive the error bounds which explicitly depend on the mesh size h$$ h $$, the time step τ$$ \tau $$ and the small dimensionless parameter ε$$ \varepsilon $$. The error estimates for the EWI‐FP methods demonstrate that their meshing strategy requirement (ε$$ \varepsilon $$‐scalability) necessitates setting h=O(1)$$ h=O(1) $$ and τ=O(ε)$$ \tau =O\left(\varepsilon \right) $$ when 0<ε≪1$$ 0<\varepsilon \ll 1 $$. Finally, some numerical examples are provided to validate the error bounds. [ABSTRACT FROM AUTHOR]

The evolution of the cathodoluminescence spectra from commercially available nanodiamonds with high density of nitrogen‐vacancy defects has been studied in a large wavelength range, from 200 to 800 nm, and temperatures from 5 to 300 K, in order to achieve a temperature probe with high spatial resolution. The full width at half maximum of the peak associated to the neutral charge state of the NV center has been found to evolve with temperature in a predictable way, although its value may vary from sample to sample. We have attributed this shift to the differences in the nanodiamonds surface chemistry. [ABSTRACT FROM AUTHOR]

Self‐protective carbonized polymer dots (CPDs) with advantageous crosslinked nano‐structures have attracted considerable attention in metal‐free room temperature phosphorescence (RTP) materials, whereas their RTP emissions are still limited to short wavelength. Expanding their RTP emissions to Near‐Infrared (NIR) range is attractive but suffers from the difficulties in constructing narrow energy levels and inhibiting intense non‐radiative decay. Herein, a crosslink‐enhanced emission (CEE)‐dominated construction strategy was proposed, achieving desired NIR RTP (710 nm) in self‐protective CPDs for the first time. Structural factors, i.e. crosslinking (covalent‐bond CEE), conjugation (conjugated amine with bridging N−H and C=C group), and steric hindrance (confined‐domain CEE), were confirmed indispensable for triggering NIR RTP emission in CPDs. Contrast experiments and theoretical calculations further revealed the rationality of the design strategy originating from CEE in terms of promoting the narrow energy level emission of triplet excitons and inhibiting the non‐radiative quenching. This work not only firstly achieves NIR RTP in self‐protective CPDs but also helps understand the origin of NIR RTP to further guide the synthesis of diverse CPDs with efficient long‐wavelength RTP emission. [ABSTRACT FROM AUTHOR]

The development of metasurfaces necessitates the rapid fabrication of nanoarrays on diverse substrates at large scales, the preparation of patterned nanoarrays on both planar and curved surfaces, and even the creation of nanoarrays on prefabricated structures to form multiscale metastructures. However, conventional fabrication methods fall short of these rigorous requirements. In this work, a novel self‐assembly hybrid manufacturing (SAHM) method is introduced for the rapid and scalable fabrication of shape‐controllable nanoarrays on various rigid and flexible substrates. This method can be easily integrated with other fabrication techniques, such as lithography and screen printing, to produce patterned nanoarrays on both planar and non‐developable surfaces. Utilizing the SAHM method, nanoarrays are fabricated on prefabricated micropillars to create multiscale pillar‐nanoarray metastructures. Measurements indicate that these multiscale metastructures can manipulate electromagnetic waves across a range of wavelengths. Therefore, the SAHM method demonstrates the potential of multiscale structures as a new paradigm for the design and fabrication of metasurfaces. [ABSTRACT FROM AUTHOR]

Infrared polarization detection has attracted wide applications in military and civilian fields by demonstrating more accurate target detection and identification capabilities due to more dimensional target information. A multifocal metalens for simultaneous detection of the polarization state of incident light at dual wavelengths is proposed based on the independent control of orthogonally polarized light. When light is incident at different wavelengths, the metalens array splits and focuses the light on three different polarization bases to form six focal points with various positions. When the incident light with varying states of polarization of dual wavelengths to be detected passes through the substrate and reaches the metalens array, the incident light detected in each wavelength forms six focal points at different positions of the focal plane of the metalens. The Stokes parameters are calculated based on the intensities of the six polarization components in the same focal plane to determine the polarization data of the azimuthal and elliptic angles of the incident light detected in each wavelength. In addition, the theoretical Stokes parameters of incident light with different polarization states at two wavelengths are compared with the reconstructed Stokes parameters, proving our method's validity. The device can directly examine the polarization state of the incident light in mid-wave infrared and long-wave infrared, significantly simplifying the polarization detection system. [ABSTRACT FROM AUTHOR]

We demonstrated high-performance 8.9 μ m cutoff wavelength nBn InAs/InAsSb type-II strained-layer superlattice (T2SL). These detectors exhibit a long minority carrier (hole) lifetime of 1.2 μ s at 80 K, high quantum efficiency of 40% for back-side illuminated devices without antireflection coating, and low dark current density of 4.6 × 10−6 A/cm2 at 80 K. We measured absorption, minority carrier (hole) lifetime, quantum efficiency, and spectral response as a function of the temperature and applied bias. We investigated the temperature dependence of the hole diffusion length and mobility and found that their values increase with temperature from 1.3 μ m and 6.5 cm2/Vs at 30 K to 6.5 μ m and 36 cm2/Vs at T = 90 K. We compared the measured diffusion length and mobility of holes in long-wavelength infrared (LWIR) T2SL with these parameters of a high-performance mid-wavelength infrared (MWIR) T2SL. Unexpectedly, hole mobility in LWIR T2SL was found to be higher than in MWIR that is contrary to the theoretical predictions. [ABSTRACT FROM AUTHOR]

All-optical nonlinear activation functions (NAFs) are crucial for enabling rapid optical neural networks (ONNs). As linear matrix computation advances in integrated ONNs, on-chip all-optical NAFs face challenges such as limited integration, high latency, substantial power consumption, and a high activation threshold. In this work, we develop an integrated nonlinear optical activator based on the butt-coupling integration of two-dimensional (2D) MoTe2 and optical waveguides (OWGs). The activator exhibits an ultra-broadband response from visible to near-infrared wavelength, a low activation threshold of 0.94 μW, a small device size (~50 µm2), an ultra-fast response rate (2.08 THz), and high-density integration. The excellent nonlinear effects and broadband response of 2D materials have been utilized to create all-optical NAFs. These activators were applied to simulate MNIST handwritten digit recognition, achieving an accuracy of 97.6%. The results underscore the potential application of this approach in ONNs. Moreover, the classification of more intricate CIFAR-10 images demonstrated a generalizable accuracy of 94.6%. The present nonlinear activator promises a general platform for three-dimensional (3D) ultra-broadband ONNs with dense integration and low activation thresholds by integrating a variety of strong nonlinear optical (NLO) materials (e.g., 2D materials) and OWGs in glass. Nonlinear activation function (NAF) devices are important for the implementation of optical neural networks. Here, the authors report the integration of 2D MoTe2 with optical waveguides to fabricate broadband all-optical NAF devices exhibiting activation thresholds down to 0.94 μW, a device size of ~50 μm2, and response rates up to 2.08 THz. [ABSTRACT FROM AUTHOR]

Macrocyclic Cu(I)–pyrazolate tetramers (Cu4pz4) can fold into compact structures with luminescent Cu4 cores whose emission wavelengths are sensitive to steric effects along the periphery of the macrocycle. Introducing CF3 at the C4 position of 3,5-di-tBu-pyrazolate increases steric crowding that modifies the conformational behavior of the Cu4pz4 complex, highlighted by a low-temperature martensitic transition. Variable-temperature analysis of solid-state luminescence reveal an unexpected blueshifting of emission with rising temperature. [ABSTRACT FROM AUTHOR]

Understanding the lattice thermal conductivity (κl) of β-Ga2O3 is very intriguing owing to its advantages in high-voltage and high-temperature applications. Despite several attempts, the underlying mechanism and causes of the notable discrepancies found in the κl values of β-Ga2O3 along [100] and [001] directions calculated using first principles remained unresolved. We demonstrate that the understanding of the nature of chemical bonding is crucial to overcome the inconsistency in theoretically reported κl values. In low-symmetry structures such as β-Ga2O3, the nature of the interactions is primarily long-range; therefore, a sufficiently large supercell inclusive of various bonding characteristics is required to capture relevant phonon wavelengths. Bonding nature-aware structure modeling allows precise estimation of acoustic and optical mode contributions towards κl. Additionally, phonon mean free path analysis confirms that considering only third-order interaction terms is adequate to determine the κl of β-Ga2O3. The calculated κl values are in excellent agreement with experimentally reported values in all three directions. Our results establish that the bonding nature and its influence on phonon scattering are essential to consider in calculating κl accurately. [ABSTRACT FROM AUTHOR]

Molecular phosphorescence in the second near‐infrared window (NIR‐II, 1000–1700 nm) holds promise for deep‐tissue optical imaging with high contrast by overcoming background fluorescence interference. However, achieving bright and stable NIR‐II molecular phosphorescence suitable for biological applications remains a formidable challenge. Herein, we report a new series of symmetric isocyanorhodium(I) complexes that could form oligomers and exhibit bright, long‐lived (7–8 μs) phosphorescence in aqueous solution via metallophilic interaction. Ligand substituents with enhanced dispersion attraction and electron‐donating properties were explored to extend excitation/emission wavelengths and enhanced stability. Further binding the oligomers with fetal bovine serum (FBS) resulted in NIR‐II molecular phosphorescence with high quantum yields (up to 3.93 %) and long‐term stability in biological environments, enabling in vivo tracking of single‐macrophage dynamics and high‐contrast time‐resolved imaging. These results pave the way for the development of highly‐efficient NIR‐II molecular phosphorescence for biomedical applications. [ABSTRACT FROM AUTHOR]

The waveguide‐integrated metasurface introduces a novel photonic chip capable of converting guided modes into free‐space light. This enables functions such as off‐chip beam focusing, steering, and imaging. The challenge lies in achieving hyper‐multiplexing across diverse parameters, including guided‐wave mode type, direction, polarization, and notably, multiple wavelengths. Here, a comprehensive end‐to‐end inverse design framework is introduced, rooted in a physical model, for the multifunctional design of on‐chip metasurfaces. This framework allows for metasurface optimization through a target‐field‐driven iteration process. A hypermultiplexed on‐chip metasurface capable of generating red‐green‐blue holograms at multiple target planes is demonstrated, with both independent and cooperative control over guided‐wave direction. Significantly, the proposed method streamlines the design process utilizing only the positions of meta‐atoms as the design variable. Nine independent holographic channels are demonstrated through a combination of wavelength and distance multiplexing. Moreover, by incorporating the excitation direction into the design, the metasurface produces a total of 36 distinct holograms. The robustness of these results against fabrication discrepancies is validated through 3D full‐wave electromagnetic simulations, aligning well with advanced manufacturing techniques. The research presents a universal design framework for the development of multifunctional on‐chip metasurfaces, opening up new avenues for a wide range of applications. [ABSTRACT FROM AUTHOR]

Understanding the lattice thermal conductivity (κl) of β-Ga2O3 is very intriguing owing to its advantages in high-voltage and high-temperature applications. Despite several attempts, the underlying mechanism and causes of the notable discrepancies found in the κl values of β-Ga2O3 along [100] and [001] directions calculated using first principles remained unresolved. We demonstrate that the understanding of the nature of chemical bonding is crucial to overcome the inconsistency in theoretically reported κl values. In low-symmetry structures such as β-Ga2O3, the nature of the interactions is primarily long-range; therefore, a sufficiently large supercell inclusive of various bonding characteristics is required to capture relevant phonon wavelengths. Bonding nature-aware structure modeling allows precise estimation of acoustic and optical mode contributions towards κl. Additionally, phonon mean free path analysis confirms that considering only third-order interaction terms is adequate to determine the κl of β-Ga2O3. The calculated κl values are in excellent agreement with experimentally reported values in all three directions. Our results establish that the bonding nature and its influence on phonon scattering are essential to consider in calculating κl accurately. [ABSTRACT FROM AUTHOR]

Aiming at the problem of limited transmission energy of liquid crystal tunable filter (LCTF), a dual-wavelength transmission system with high signal-to-noise ratio (SNR) is proposed in this paper. The proposed transmission factor Qp is the main influence on the number and location of transmission wavelengths as well as the bandwidth of each transmission wavelength for dual-wavelength systems. Dual-wavelength LCTF can improve the effective transmission energy of the system by increasing the number of filtering channels, and the transmission energy can be increased by about 1.8 times and 70% at short and long wavelengths, respectively, which improves the signal-to-noise ratio (SNR) of the system. Moreover, the dual-wavelength LCTF system is even possible to increase the transmission energy by about 7% at a 33% increase in spectral resolution. Therefore, the dual-wavelength LCTF transmission method not only can improve the SNR of target detection with dual-wavelength response features, but also can effectively solve the problem of contradiction between spectral resolution and spectral transmission energy. [ABSTRACT FROM AUTHOR]

The polarized bidirectional reflectance distribution function (pBRDF) can describe the changes between the Stokes vectors of incident and reflected light. The existing model can only describe the spatial distribution of the target's polarization characteristics at a single wavelength, so further research is needed for the description of the target's polarized spectral characteristics. In this paper, a modified three-component polarized spectral bidirectional reflectance distribution function (pSBRDF) is proposed, which combines Fresnel equation in the specular reflection component with Cauchy's empirical dispersion equation, by introducing the wavelength variable and dispersion constants that do not change with wavelength. The degree of the linear polarization (DoLP) of two types of coated fabric samples was measured at three incident angles and 400 to 760 nm wavelength. The error of the model in describing the spectral and the spatial distribution of DoLP are controlled within 0.00743 and 0.0757 respectively, which proves the accuracy of the model. This research provides the model basis for analysis of the target's polarization characteristics and the theoretical basis for the application of polarization detection. [ABSTRACT FROM AUTHOR]

This work shows how to control the surface density and size of InAs/InP quantum dots over a wide range by tailoring the conditions of Stranski-Krastanov growth. We demonstrate that in the near-critical growth regime, the density of quantum dots can be tuned between 10 7 and 10 10 cm - 2 . Furthermore, employing both experimental and modeling approaches, we show that the size (and therefore the emission wavelength) of InAs nanoislands on InP can be controlled independently from their surface density. Finally, we demonstrate that our growth method gives low-density ensembles with well-isolated QD-originated emission lines in the telecom C-band. [ABSTRACT FROM AUTHOR]

Silicon, carbon and oxygen hybrid nanomaterials (i.e., SiCOHNs) have recently drawn extensive attention as versatile photoluminescence (PL) nanosystems. The collective advantages of silicon‐ and carbon‐based nanostructures have resulted in SiCOHNs with tunable and photostable PL properties, abundant possibilities for surface modification, and low biotoxicity. Although SiCOHNs have shown great potential in diverse applications, such as bioimaging, biosensing, drug delivery and information encryption, discovering novel SiCOHNs with explicit nanostructures and elucidating the fundamental mechanisms of their PL properties for bioapplications are highly desirable. In this review, on the preparation of SiCOHNs on the basis of the synthesis conditions and precursors are first focused. Next, the manipulation of the emission wavelength, quantum yield and RTP of SiCOHNs is discussed. On the basis of previous reports and the recent experimental/theoretical results, the primary structure of SiCOHNs is clarified and deduced their possible PL mechanism. SiCOHNs possess bacterial uptake efficiency and/or anticancer capacity, promoting various biomedical applications and proof‐of‐concept applications in anti‐counterfeiting. Finally, current challenges and future trends are summarized as a roadmap for the development of SiCOHNs‐based optical applications. [ABSTRACT FROM AUTHOR]

We demonstrate scalable ultra-strong light–matter coupling with intersubband polaritons in a truly harmonic confining potential. The harmonicity grants immunity from electron–electron interactions, a protection guaranteed by the Kohn theorem, allowing the intersubband transition frequency to be lowered while keeping the light–matter interaction strength constant. In principle, this procedure permits increasing the relative coupling strength (η = ΩRabi/ω12) at will. We measure a record low intersubband transition at 1.24 THz and a lower polaritonic mode at 920 GHz, below the barrier of 1 THz. The system exhibits a η ratio of 0.24, fully in the ultra-strong coupling regime, and remains stable up to 78 K. This approach is valuable for future non-adiabatic quantum electrodynamic experiments at long wavelengths. [ABSTRACT FROM AUTHOR]

Broadband green phosphors have important applications in overcoming the blue-green (cyan) 470–510nm gap of phosphor-converted white LED (pc-WLED) and achieving high color rendering index (CRI) white lighting. In this work, a broadband green phosphor La2W2O9: xBi3+ was synthesized by solid-state method. The phase, morphology and luminescence properties of the series of phosphors were systematically studied. The results showed the La2W2O9: xBi3+ green phosphor exhibits a wide emission band in the range of 400–800nm with full width at half-maximum (FWHM) of 164nm, filling the cyan gap and reaching its peak at 550nm. The phosphor exhibits broadband excitation, and the excitation range covers the wavelength region of 200–500nm, and matches well with commercial ultraviolet LED. With the obtained broadband green phosphor, commercial CaAlSiN3:Eu2+ red phosphor, commercial BaMgAl10O17:Eu2+ blue phosphor, and a 365nm commercial chip, a warm white pc-WLED device with a high color-rendering index (Ra=97.4, R1–R15>90) and low correlated color temperature (CCT=3610K) was fabricated. The results demonstrate the wide range of applications for La2W2O9:Bi3+ phosphor in the field of premium warm white LED lighting. [ABSTRACT FROM AUTHOR]

A chiral meta‐optics platform that incorporates hologram‐multiplexing with low phase distortion and wide‐incident angle tolerance over the broad spectral range of the ultraviolet‐visible (UV–vis) regimes holds great potential for photonic‐encryption‐based applications, particularly in next‐generation 3D displays, high‐resolution biomedical imaging, holographic anti‐counterfeiting labeling, and multi‐channel optical communication. However, the design incorporating giant chirality from UV–vis wavelengths coupled with wide‐incident‐angle tolerance and cost‐effective fabrication is still challenging. Here, the study introduces a pragmatic multifunctional dielectric chiral meta‐platform designed for simultaneous spin‐ and wavelength‐multiplexing of optical information in the UV–vis spectrum. The unit cell comprises a dimer structure based on wide‐bandgap silicon nitride (SiNx), ensuring substantial dual‐spectrum chiro‐optical effects. The meticulously engineered chiral meta‐platform offers an incident angle tolerance of up to 40 degrees, coupled with significant chiro‐optical transmission. To demonstrate the concept, two distinct phase profiles are embedded in the meta‐platform, utilizing the spin and wavelength of incident light as keys to unlock the specific holographic information. The chiral meta‐platform is experimentally validated for oblique illumination angles, showcasing its adaptability across the UV–vis spectrum. The demonstrated meta‐device with dual‐spectrum visual encryption can be applied in various anti‐counterfeiting and security applications. [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]

To investigate the rolling wave characteristics of overland flow, this study calibrated the accuracy of the depth measurement system for shallow flow on slopes using acrylic sheets and optimized it as a dual-line laser water depth measurement system. Non-contact measurement methods were used to measure the water depth at the mature cross-section position of rolling waves in real time. This experiment designed a total of 5 measurement intervals, namely 0.04, 0.05, 0.10, 0.15, and 0.20 m. Three horizontal gradients were set for the slope, namely 3°, 9°, and 15°, and six horizontal gradients were set for the flow rate, namely 2, 4, 8, 12, 16, and 20 L/min. Each horizontal gradient was repeated for 5 experiments. The results indicated that the accuracy of the depth measurement system for shallow flow on slopes was confirmed to be 0.473 mm per grid, and the optimal spacing for the dual-line laser depth measurement system was 0.04 m. Both flow rate and slope significantly affected the wave speed, wave height, height difference, and frequency of rolling waves. The influence of flow rate (the effect size values were 0.655-0.963) was greater than that of slope (the effect size values were 0.232-0.874). The slope significantly affected the wavelength, while the flow rate did not significantly impact it. Wave speed increased with flow rate but the influence of flow rate on wave speed decreased with increasing slope. Under different slope conditions, wave height responded differently to flow rate. At a 3° slope, wave height initially increased and then decreased with increasing flow rate, whereas at higher slopes (9° and 15°), the wave height increased significantly under low flow conditions (2-8 L/min), with the increases of 3.74 and 4.63 mm, respectively. The difference in wave height between 3° and 9° slopes increased with flow rate, but the difference between 9° and 15° slopes decreased. The variation in height difference with slope was influenced by flow rate, showing a trend of initially increasing and then decreasing. Increased flow rates led to an increase in frequency, with the largest increase at a 15° slope, up to 2.37 Hz. The frequency differences between slopes decreased and then increased as flow rate increased, with a critical flow rate of 8 L/min. At a low slope (3°), wavelength fluctuated with flow rate, whereas at a high slope (15°), higher flow rates inhibited the development of wavelength. Under the high flow conditions (16-20 L/min), the wavelength differences between slopes were significant. This research provides a theoretical basis for improving the accuracy of slope overland flow measurements and further elucidating the dynamic characteristics of overland flow rolling waves. [ABSTRACT FROM AUTHOR]

Polarization state generation plays an important role in optics and are applied in many fields. Multispectral polarization manipulation can increase information capacity. To meet the requirement of miniaturization and integration, it is desirable to generate multispectral polarization states with a compact optical device. a metasurface device is proposed and experimentally demonstrated, which can simultaneously realize wavelength separation and polarization generation. A geometric metasurface is used to realize the phase and wavelength multiplexing. Six polarization states with different wavelengths are generated. Customized polarization states with predesigned wavelength information can add extra degrees of freedom for carrying information, opening a new window for portable polarization optics where low‐cost and miniaturized systems are in high demand. [ABSTRACT FROM AUTHOR]

2‐(3,6‐Bis(4‐methoxyphenyl)‐2,2,5,5‐tetramethyl‐4‐oxo‐4,5‐dihydropentalen‐1(2H)‐ylidene)malononitrile (DPM‐An) and 2,2′‐(3,6‐bis(4‐methoxyphenyl)‐2,2,5,5‐tetramethyl‐2,5‐dihydropentalene‐1,4‐diylidene)dimalononitrile (DPD‐An), both bearing the 2,5‐dihydropentalene core and intramolecular electron donor–acceptor moieties, were prepared and subjected to photophysical studies. The absorption spectra of DPM‐An and DPD‐An in CH2Cl2 at room temperature contain maxima at similar wavelengths of 406 and 409 nm, respectively. These substances do not luminesce in CH2Cl2 solution at room temperature, but they do emit light when present in poly(methyl methacrylate) films. Interestingly, DPM‐An and DPD‐An in the film forms display nearly identical emission (EM) spectra with respective maxima at 592 and 594 nm. In contrast, DPD‐An has a longer EM lifetime than does DPM‐An. Therefore, the dihydropentalene derivatives, exemplified by DPM‐An and DPD‐An, may be a family of substances in which excited state decay rate can be varied without changing EM wavelengths. [ABSTRACT FROM AUTHOR]

Optical metamaterials have revolutionized imaging capabilities by manipulating light‐matter interactions at the nanoscale beyond the diffraction limit. Bilayer nanowire grating configurations exhibit significant potential as exceptional elements for high‐performance polarimetric imaging systems. However, conventional computational approaches for predicting electromagnetic responses are time‐consuming and labor‐intensive, and thereby, the practical implementation remains challenging through an iterative design, analysis, and fabrication process. Here, a deep learning‐based design process is presented utilizing an artificial neural network (ANN) trained on finite element method (FEM) simulations that enables the prediction of bilayer nanowire gratings‐based electromagnetic responses. The study validates predictions through nanoimprinted bilayer nanowire gratings, demonstrating the reliability of the ANN's predictions. Furthermore, the research identifies critical geometric parameters significantly influencing transverse magnetic (TM) and transverse electric (TE) transmission. The ANN model effectively tailors design for specific mid‐wavelength infrared (MWIR) wavelengths, which may provide a practical tool for rapidly designing and optimizing metamaterial for high‐performance polarizers. [ABSTRACT FROM AUTHOR]

Palmprint as biometrics has gained increasing attention recently due to its discriminative ability and robustness. However, existing methods mainly improve palmprint verification within one spectrum, which is challenging to verify across different spectrums. Additionally, in distributed server-client-based deployment, palmprint verification systems predominantly necessitate clients to transmit private data for model training on the centralized server, thereby engendering privacy apprehensions. To alleviate the above issues, in this paper, we propose a physics-driven spectrum-consistent federated learning method for palmprint verification, dubbed as PSFed-Palm. PSFed-Palm draws upon the inherent physical properties of distinct wavelength spectrums, wherein images acquired under similar wavelengths display heightened resemblances. Our approach first partitions clients into short- and long-spectrum groups according to the wavelength range of their local spectrum images. Subsequently, we introduce anchor models for short- and long-spectrum, which constrain the optimization directions of local models associated with long- and short-spectrum images. Specifically, a spectrum-consistent loss that enforces the model parameters and feature representation to align with their corresponding anchor models is designed. Finally, we impose constraints on the local models to ensure their consistency with the global model, effectively preventing model drift. This measure guarantees spectrum consistency while protecting data privacy, as there is no need to share local data. Extensive experiments are conducted to validate the efficacy of our proposed PSFed-Palm approach. The proposed PSFed-Palm demonstrates compelling performance despite only a limited number of training data. The codes have been released at https://github.com/Zi-YuanYang/PSFed-Palm. [ABSTRACT FROM AUTHOR]

m‐Pyripentaphyrins(1.0.0.0.0) were synthesized by Suzuki‐Miyaura coupling of 3,5‐bis(5‐borylpyrrol‐2‐yl)‐BODIPY with 2,6‐dibromopyridine. Upon treatment with PhBCl2, pyripentaphyrin 1 provided mono‐ and bis‐BIII complexes sequentially. The Mono‐BIII complex shows a distorted tetrahedral coordinated BIII with a σ‐phenyl ligand on the BIII and the bis‐BIII complex shows an additional distorted tetrahedral coordinated BIII with a B−H bond. Bromination of the pyripentaphyrins with N‐bromosuccinimide (NBS) resulted in regioselective formation of 8‐bromopyripentaphyrins, which were dimerized to 8,8'‐linked dimers by reductive coupling with Ni(cod)2. While all these pyripentaphyrins are nonaromatic, they exhibit characteristic broad absorption bands at long wavelength near the NIR region, indicating the presence of effective macrocyclic conjugation. [ABSTRACT FROM AUTHOR]

Broadband near‐infrared (NIR) phosphors have garnered significant attention due to their potential applications in phosphor‐concerted NIR light‐emitting diodes (pc‐NIR‐LEDs). Cr3+‐doped NIR phosphors are particularly intriguing because of their broad NIR emission and high efficiency. However, reports on Cr3+‐doped NIR‐II (900–1700 nm) phosphors are scarce. In this study, a novel Cr3+‐doped SrLaGa3O7 NIR‐II phosphor is presented, where the Cr3+ ions are located at tetrahedral sites. The full width at half maximum (FWHM), peak wavelength, internal quantum efficiency (IQE), and thermal activation energy (ΔE) for the synthesized SrLaGa3O7:0.9%Cr3+ phosphor are 194 nm, 1167 nm, 76.12%, and 0.269 eV, respectively. The substitution of Sc3+ for Ga3+ enhances the luminescence performance, and the 0.9%Cr3+/3%Sc3+ co‐doped SrLaGa3O7 phosphor exhibits a peak wavelength of 1208 nm, an IQE of 92.78%, and a ΔE of 0.285 eV. Furthermore, the sintering process in the air induces a transition from Cr3+ to Cr4+, resulting in the formation of SrLaGa3O7:0.9%Cr4+ phosphor, which has a peak wavelength of 1270 nm and an FWHM of 305 nm. The potential application of the 0.9%Cr3+/3%Sc3+ co‐doped SrLaGa3O7 phosphor in pc‐NIR‐LEDs is also evaluated. [ABSTRACT FROM AUTHOR]

Low‐toxic multinary semiconductor quantum dots (QDs) showing a photoresponse in a wide wavelength range from visible to near‐IR wavelength regions have been intensively investigated for fabricating efficient solar light conversion systems. Recently, AgBiS2 QDs have attracted much attention for their application to improve the performance of QD solar cells because they have a large absorption coefficient in the visible and near‐IR regions. In this report, we describe solution‐phase preparation of ternary Ag−Bi−S QDs with different sizes and with different Ag/Bi ratios. The average size of resulting spherical Ag−Bi−S QDs was controllable from 2.7 to 8.1 nm by adjusting the reaction temperature from 373 to 473 K, while the Ag fraction of obtained QDs also increased with an increase in particle size. The absorption onset wavelength shifted from 850 to 1200 nm in the near‐IR region as the particle size increased. AgBiS2 QDs with an almost stoichiometric composition, obtained at reaction temperatures of 423 K and 473 K, contained no deep intragap states and exhibited a p‐type semiconductor behavior, while QDs prepared at a reaction temperature of 393 K or lower had non‐stoichiometric Ag‐deficient compositions producing intragap defect states. Sensitized solar cells fabricated with stoichiometric AgBiS2 QDs exhibited a photoresponse in visible and near‐IR wavelength regions, the optimal PCE being 0.74% with AgBiS2 QDs of 6.2 nm in diameter that were prepared at 423 K. [ABSTRACT FROM AUTHOR]

A PCF (photonic crystal fiber) with high birefringence and single-mode polarization retention over a wide wavelength range is designed and studied. The birefringence and polarization retention characteristics of the PCF base mode were studied using FVFEM (full vector finite element method) and APML (anisotropic perfect matching layer) as boundary conditions. The simulation results show that by rotating the elliptical air hole parallel to the horizontal axis by 45°, and then rotating the elliptical air hole parallel to the longitudinal axis by 45°, the birefringence of the PCF obtained is as high as 4.7 × 10−2, and it has good single model ability, which can be used for various optical devices. [ABSTRACT FROM AUTHOR]

This article presents the refractive index (RI) sensitivity study of cladding reduced uniform long-period fiber grating. The displacement of resonant wavelength with the change in ambient RI is observed to inspect the sensitivity. Here, the grating period is fixed at a value (550 μm) to analyze RI sensitivity of cladding modes (HE13-HE14). However, it varies in earlier mathematical studies to adjust the resonant wavelength of all modes at a specific wavelength. The three-layer fiber geometry-based mathematical approach is employed to estimate the core and cladding modes. The obtained results support decline in quantity of cladding modes sustained by a single-mode fiber. The decrease in cladding radius has shown enhancement in RI sensitivity. For a reduction of 22 μm in cladding radius, the highest ordered HE14 cladding mode has shown 5.8 times improvement in its sensitivity. [ABSTRACT FROM AUTHOR]

The study on evolutionary dynamics of Mid-Channel Bars (MCBs) under regulated-river regime is surprisingly scanty. To bridging this gap, morphological variables of 32 MCBs and channel parameters of a reach of ∼75.83 km of Bhagirathi-Hooghly River were examined over a time span of 30 years. For quantifying MCBs dimensions, satellite imageries and Google earth pro images were used under GIS environment. Bivariate-Correlation and Variability in MCB parameters were assessed using goodness-of-fit measures (R2) and CV or σ respectively. It is found that over time, the number and area of MCBs has been increased 3.56 times from 9 in 1990 to 32 in 2023. The reach of the river is on the way of transformation form meandering one to the braiding one. Both frequency of MCBs and braiding intensity show an increasing trend towards downstream. It is found that there was more than 1 MCBs within a wavelength in 2023 and it was much less in 1990 (0.3).The temporal variability in size of MCBs shows that smaller MCBs are more variable than larger one. Stability of larger MCBs are attributedto the impact of permanently grown vegetation. Dynamics in MCBs shape do not show any significant spatio-temporal trend. The larger MCBs are more circular than smaller ones attributing to the lateral accumulation of sediments under vegetated MCB margins. This work suggests that continued investigation into the MCB dynamics is to be substantiated by more advanced technology-based interdisciplinary approaches based on robust data. [ABSTRACT FROM AUTHOR]

Shock waves, characterized by abrupt changes in pressure, temperature, and density, play a significant role in various materials science processes involving fluids. These high-energy phenomena are utilized across multiple fields and applications to achieve unique material properties and facilitate advanced manufacturing techniques. Accurate simulations of these phenomena require numerical schemes that can represent shock waves without spurious oscillations and simultaneously capture acoustic waves for a wide range of wavelength scales. This work suggests a high-order discontinuous Galerkin (DG) method with a finite volume (FV) subcell limiting strategies to achieve better subcell resolution and lower numerical diffusion properties. By switching to the FV discretization on an embedded sub-cell grid, the method displays advantages with respect to both DG accuracy and FV shock-capturing ability. The FV scheme utilizes a class of high-fidelity schemes that are built upon the boundary variation diminishing (BVD) reconstruction paradigm. The method is therefore able to resolve discontinuities and multi-scale structures on the subcell level, while preserving the favorable properties of the high-order DG scheme. We have tested the present DG method up to the 6th-order accuracy for both smooth and discontinuous noise problems. [ABSTRACT FROM AUTHOR]

Millipedes increase the duty ratio and wavelength of their gait to enhance thrust force against resistive load. However, the underlying control mechanisms responsible for generating such adaptive gaits remain elusive. In this study, we proposed a decentralized control law based on the concept of ‘discrepancy function’. Our proposed walking controller successfully reproduced the load-adaptive gaits of millipedes on the inclined ground. Furthermore, we evaluated the adaptability of our controller to horizontal resistive forces that hinder forward walking. Our simulation results suggest that the millipede-inspired controller could be beneficial for multi-legged robots equipped with leg actuators operating under limited motor outputs. [ABSTRACT FROM AUTHOR]

Chromaticity-tunable random lasers (RLs) have wide applications in laser display and imaging. However, the achievable chromaticity range poses challenges due to their inherent randomness and the inevitable loss. Here, an ultrabroadband chromaticity-programmable RL has been demonstrated via waveguide-assisted pumping strategy. The unique configuration with destroyed waveguide supplies an excellent platform for achieving full color random lasing through the cascade pumping process. Random lasing with tunable wavelengths spanning the entire visible range is achieved via side-pumping schemes. The eight acceptor RLs can be simultaneously pumped to obtain chromaticity-programmable random lasing, showcasing a Commission Internationale de l'Eclairage (CIE) color map with 155% more perceptible colors than the standard red-green-blue space. This opens the possibilities for programmable RLs with potential applications in biological imaging and smart sensing. [ABSTRACT FROM AUTHOR]

Summary In this paper, a 4 × 4 MIMO (multiple‐input multiple‐output) antenna with metasurface (MS), which is composed of dual circularly polarized (CP) patch antennas, is proposed for 5G (sub‐6 GHz) applications. The MIMO antenna consists of four microstrip patch antennas. In order to improve the isolation of the MIMO antenna, parasitic elements are placed on the MS and layer of patch antennas. In addition, a substrate‐integrated waveguide (SIW) structure is used at the center of the MIMO antenna for this purpose. The proposed MIMO antenna is fabricated for validation tests. The antenna has overall dimensions of 115 mm × 115 mm × 3.2 mm (1.219 λ0$$ {\lambda}_0 $$ × 1.219 λ0$$ {\lambda}_0 $$ × 0.033 λ0$$ {\lambda}_0 $$, where λ0$$ {\lambda}_0 $$ is the free space wavelength at the lowest operating frequency in 10‐dB impedance bandwidth). The MIMO antenna has 10‐dB impedance bandwidth (IBW) from 3.3 to 3.8 GHz (14.08%), 3‐dB axial ratio bandwidth (ARBW) from 3.42 to 3.69 GHz (7.59%), and 6.36‐dBi peak gain. The isolation is greater than 28.14 dB in the n78 frequency band (3.3–3.8 GHz). [ABSTRACT FROM AUTHOR]

Halogen-containing bridged carborane–tetraphenylethene compounds have been synthesized by the chlorination of the corresponding tetraphenylethene–carboranylmethanol. The fluorinated compound 1 shows interesting excitation-dependent emission (ex-de) properties in various aggregate states, i.e. powder before and after grinding, ground-fuming and ground-annealing, whereas the non-fluorinated analog compound 2 displays ex-de properties only after grinding. The carborane cluster, bridging group and halogen atoms cooperatively tune the emission properties of these compounds. Compound 1 has good crystallinity and multiple interactions in the molecular packing, thus in various aggregate states a mixture of crystalline and amorphous particles in an uncertain ratio renders the samples the corresponding ex-de properties, and compound 2 shows ex-de properties due to a similar reason. Compounds 1 and 2 exhibit typical aggregation-induced emission properties as they have tetraphenylethene moieties, and good photoluminescence quantum yields in the solid state (0.54, 1; 0.39, 2) being relatively high when compared to those of the reported carborane derivatives with ex-de properties. In addition, compound 1 shows a relatively wide-range emission wavelength shift (maximum 73 nm) at various excitation wavelengths. These results suggest a new convenient approach to synthesize various compounds with ex-de properties. [ABSTRACT FROM AUTHOR]

We proposed a novel fiber Mach–Zehnder interferometer (FMZI) that can perform an ultrahigh extinction ratio (ER), ultracompact, and ultra-broadband interference characteristics. The FMZI structure is based on an extremely tiny hollow core fiber (HCF) with a small diameter of 10 μm (named HCF10) connected with a beam splitter of a large core of 50 μm HCF (named HCF50). The refractive index (RI) of the air core is lower than that of the HCF cladding; a leaky-guided fiber waveguide (LGFW) occurs in such a short-section HCF10 waveguide to simultaneously have the core and cladding modes. To achieve better fringe visibility of the interference, the section of HCF50 assists in splitting the optical light into core and cladding beams launched into the HCF10 with appropriate intensities. Experimental and simulation results show that the optical characteristics of the proposed LGFW-FMZI are very similar. Based on the results of the study, the length of the HCF10 primarily influences the free spectral range (FSR) of the interference spectra, and the HCF50 splitter significantly controls the optimal extinction ratio (ER) of the interference fringes. By exactly adjusting the lengths of HCF10 and HCF50, the proposed fiber interferometers can perform the capability of an ultrahigh ER over 50 dB with the arbitrary FSR in the transmitted interference spectra over an ultra-broad wavelength range of 1250 nm to 1650 nm. [ABSTRACT FROM AUTHOR]

The synthesis of 2D MoWS2 nanosheets involved the liquid-phase exfoliation technique was explored in this paper. The nonlinear optical response of MoWS2 was characterized in the 1 µm wavelength range, and its suitability as a saturable absorber (SA) was confirmed. Experimental demonstrations were conducted by using MoWS2 as an SA in an idler-resonant intracavity KTA optical parametric oscillator (OPO) driven by a dual-loss-modulated Q-switched and mode-locked (QML) YVO4/Nd:YVO4 laser with an acousto-optic modulator (AOM). By appropriately tuning the pump power and the AOM repetition rate, the Q-switched envelope pulse widths for the signal and idler waves could be significantly reduced to be shorter than the cavity round-trip transit time, i.e., the interval between two neighboring mode-locking pulses. Consequently, this enabled the generation of sub-nanosecond single mode-locking pulses with a low repetition rate, high pulse energy, and remarkable stability. With a repetition rate of 1 kHz and maximal pulse energies of 318 µJ and 169 µJ, respectively, sub-nanosecond single mode-locking pulses of the signal and idler waves were generated. The theoretical model was established using coupled rate equations with a Gaussian spatial distribution approximation. The numerical simulation results for generating sub-nanosecond single mode-locking pulses for the signal and idler waves within their respective Q-switched envelopes aligned fundamentally with the experimental results, proving that MoWS2 can be a potential nanomaterial for further optoelectronic applications. [ABSTRACT FROM AUTHOR]

We used NASA's high-resolution (1/48° or 2.3 km, hourly) Estimating the Circulation and Climate of the Ocean (ECCO) estimates of salinity at a 1 m depth from November 2011 to October 2012 to detect semi-diurnal and diurnal internal tides (ITs) in the Andaman Sea and determine their characteristics in three 2° × 2° boxes off the Myanmar coast (box A), central Andaman Sea (box B), and off the Thailand coast (box C). We also used observed salinity and temperature data for the above period at the BD12-moored buoy in the central Andaman Sea. ECCO salinity data were bandpass-filtered with 11–14 h and 22–26 h periods. Large variations in filtered ECCO salinity (~0.1 psu) in the boxes corresponded with near-surface imprints of propagating ITs. Observed data from the box B domain reveals strong salinity stratification (halocline) in the upper 40 m. Our analyses reveal that the shallow halocline affects the signatures of propagating semi-diurnal ITs reaching the surface, but diurnal ITs propagating in the halocline reach up to the surface and bring variability in ECCO salinity. In box A, the semi-diurnal IT characteristics are higher speeds (0.96 m/s) with larger wavelengths (45 km), that are closer to theoretical mode 2 estimates, but the diurnal ITs propagating in the box A domain, with a possible source over the shelf of Gulf of Martaban, attain lower values (0.45 m/s, 38 km). In box B, the propagation speed is lower (higher) for semi-diurnal (diurnal) ITs. Estimates for box C are closer to those for box A. [ABSTRACT FROM AUTHOR]