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C30H36F2N6O9S, orthorhombic, P212121 (no. 19), a = 5.2364(8) Å, b = 10.0250(14) Å, c = 59.689(9) Å, V = 3133.4(8) Å3, Z = 4, Rgt(F) = 0.0384, wRref(F2) = 0.0969, T = 170 K.

C22H23NO3, triclinic, P1‾$P\overline{1}$ (no. 2), a = 9.6505(4) Å, b = 9.9712(5) Å, c = 10.0845(4) Å, α = 68.177(4)°, β = 88.106(3)°, γ = 79.234(4)°, V = 884.30(7) Å3, Z = 2, Rgt(F) = 0.0424, wRref(F2) = 0.1150, T = 293 K.

C13H10N4O7, monoclinic, P21/n (no. 14), a = 10.7017(7) Å, b = 7.1240(5) Å, c = 19.0878(13) Å, β = 99.280(3)°, V = 1436.19(17) Å3, Z = 4, Rgt (F) = 0.0586, wRref (F 2) = 0.1746, T = 296.15 K.

C20H24N2O8, monoclinic, P21/n (no. 14), a = 3.8981(3) Å, b = 16.0675(11) Å, c = 16.2908(10) Å, β = 94.537(3)°, V = 1017.14(12) Å3, Z = 2, R gt(F) = 0.0634, wR ref(F 2) = 0.1746, T = 170 K.

C10H14O6, triclinic, P1‾ $P\overline{1}$ (no. 2), a = 7.5531(2) Å, b = 9.3964(3) Å, c = 9.5089(3) Å, α = 61.8330(10)°, β = 68.6230(10)°, γ = 86.5750(10)°, V = 548.80(3) Å3, Z = 2, R gt(F) = 0.0485, wRref (F 2) = 0.1438, T = 170.0 K.

C12H13N3O7, triclinic, P1‾ $P\overline{1}$ (no. 2), a = 6.9878(9) Å, b = 7.0956(8) Å, c = 13.8113(15) Å, α = 88.745(5)°, β = 87.764(5)°, γ = 75.785(5)°, V = 663.27(14) Å3, Z = 2, Rgt (F) = 0.0455, wRref (F 2) = 0.1264, T = 296.15 K.

Stimulated emission depletion (STED) microscopy breaks the optical diffraction barrier and has become a powerful tool for biological study. However, its application for in vivo study is limited because of its high demand for depletion power. Here, we propose digitally enhanced STED (DE-STED) as a method for reducing the depletion power that is required for STED superresolution imaging. A donut image is the key in this approach, which is composed of the depleted photons by STED laser and represents the intensity difference between confocal and STED images from the same imaging position. The depletion efficiency is digitally enhanced by multiplying the intensity of the donut image with a factor greater than 1, and then the photons from the periphery of the diffraction-limited spot are fully depleted by subtracting the enhanced donut image from the original confocal image. Finally, DE-STED achieves a resolution of ~λ/8 in biological samples with a depletion power that is an order of magnitude lower than that in traditional STED imaging. Furthermore, the proposed method helps to relax the restrictions on the fluorophore because of its low phototoxicity and photobleaching.

C25H18F3NO3S, orthorhombic, Pca21 (no. 29), a = 19.1142(7) Å, b = 11.6722(5) Å, c = 9.2390(3) Å, V = 2061.26(13) Å3, Z = 4, Rgt(F) = 0.0422, wRref(F2) = 0.0974, T = 100.02(10) K.

With a purely optical modulation of fluorescent behaviors, stimulated emission depletion (STED) microscopy allows for far-field imaging with a diffraction-unlimited resolution in theory. The performance of STED microscopy is affected by many factors, of which aberrations induced by the optical system and biological samples can distort the wave front of the depletion beam at the focal plane to greatly deteriorate the spatial resolution and the image contrast. Therefore, aberration correction is imperative for STED imaging, especially for imaging thick specimens. Here, we present a wave front compensation approach based on the genetic algorithm (GA) to restore the distorted laser wave front for improving the quality of STED images. After performing aberration correction on two types of zebrafish samples, the signal intensity and the imaging resolution of STED images were both improved, where the thicknesses were 24 μm and 100 μm in the zebrafish retina sample and the zebrafish embryo sample, respectively. The results showed that the GA-based wave front compensation approach has the capability of correction for both system-induced and sample-induced aberrations. The elimination of aberrations can prompt STED imaging in deep tissues; therefore, STED microscopy can be expected to play an increasingly important role in super-resolution imaging related to the scientific research in biological fields.

This paper investigates the problem of reactive power sharing based on virtual flux droop method. Firstly, flux droop control method is derived, where complicated multiple feedback loops and parameter regulation are avoided. Then, the reasons for inaccurate reactive power sharing are theoretically analyzed. Further, a novel reactive power control scheme is proposed which consists of three parts: compensation control, voltage recovery control and flux droop control. Finally, the proposed reactive power control strategy is verified in a simplified microgrid model with two parallel DGs. The simulation results show that the proposed control scheme can achieve accurate reactive power sharing and zero deviation of voltage. Meanwhile, it has some advantages of simple control and excellent dynamic and static performance.

Expanding ring experiment is an important method for dynamic fragmentation of solid under 1D tensile loading. Based on the split Hokinson pressure bar (SHPB), a liquid-driving experimental technology was developed for conducting expanding ring tests. The loading fixture includes a hydraulic cylinder filled with water, which is pushed by a piston connected to the input bar. As the water is driven, it expands the metallic ring specimen in the radial direction. The approximately incompressible property of the water makes it possible to drive the specimen in very high radial velocity by low velocity movement of piston, according to the large sectional area ratio of the cylinder to specimen. Using liquid-driving expanding ring device, 1060 aluminum rings (ductile materials)/PMMA rings (brittle materials) were fragmented and the fragments were recovered. Impact deformation of free-flying fragments was avoided through the use of “sample soft-capture” technology. The fragmentation process was observable by high speed camera through modifying the driving direction of the water. From the observations of the fracture morphology and the residual internal cracks of the recovered fragments, it is concluded that the fracture of the rings is caused by the circumferential tensile stress.

Based on two-band isotropic Ginzburg-Landau theory, we study the temperature dependence of upper critical field and London penetration depth for non-centrosymmetric superconductor LaNi[C.sub.2]. All the theoretical calculations fit the experimental data very well, especially the upward curvature of upper critical field near the critical temperature. Our results thus indicate that the two-gap scenario is better to account for the superconductivity of LaNi[C.sub.2], and the Cooper pairs of this superconductor are in the conventional s-wave state. Key words: non-centrosymmetric superconductor, Ginzburg-Landau theory, upper critical field, London penetration depth. Sur la base de la theorie isotrope a deux bandes de Ginzberg-Landau, nous etudions la dependance en temperature du champ critique superieur et de la profondeur de la penetration de Landau pour le supraconducteur non centro-symetrique LaNi[C.sub.2]. Tous les calculs theoriques sont en tres bon accord avec les valeurs experimentales, specialement la courbure superieure du champ critique superieur pres de la temperature critique. Nos resultats indiquent ainsi que le scenario a deux bandes est le meilleur pour decrire la supraconductivite de LaNi[C.sub.2] et que la paire de Cooper est dans l'etat conventionnel de l'onde s. [Traduit par la Redaction] Mots-cles: supraconducteur non centro-symetrique, theorie de Ginzberg-Landau, champ critique superieur, profondeur de la penetration de London, scenario a deux bandes., 1. Introduction In the past 10 years, non-centrosymmetric superconductors have gained huge interest since the discovery of superconductivity in heavy-fermion material Ce[Pt.sub.3]Si [1]. For the superconductors with unbroken inversion symmetry, [...]

Abstract Repeating a gate sequence multiple times amplifies systematic errors coherently, making it a useful tool for characterizing quantum gates. However, the precision of such an approach is limited by low-frequency noise, while its efficiency is hindered by time-consuming scans required to match up the phases of the off-diagonal matrix elements being amplified. Here, we overcome both challenges by interleaving the gate of interest with dynamical decoupling sequences in a protocol we call Matrix-Element Amplification using Dynamical Decoupling (MEADD). Using frequency-tunable superconducting qubits from a Google Sycamore quantum processor, we experimentally demonstrate that MEADD surpasses the accuracy and precision of existing characterization protocols for estimating systematic errors in single- and two-qubit gates. We use MEADD to estimate coherent parameters of CZ gates with 5 to 10 times the precision of existing methods and to characterize previously undetectable coherent crosstalk, reaching a precision below one milliradian.

As a noninvasive and label-free optical technique, Raman spectroscopy offers significant advantages in studying the structure and properties of biomacromolecules, as well as real-time changes in cellular molecular structure. However, its practical applications are hindered by weak scattering responses, low signal intensity, and poor spectral uniformity, which affect the subsequent accuracy of spectral analysis. To address these issues, we report a novel surface-enhanced Raman scattering (SERS) substrate based on a pyramidal pitted silicon (PPSi) array structure adhered with Au-shell Ag-core nanospheres (Au@Ag NSs). By preparing a highly uniform PPSi array substrate with controllable size and arrangement, and constructing SERS-active Au@Ag NSs on this substrate, a three-dimensional (3D) composite SERS substrate is realized. The enhancement performance and spectral uniformity of 3D composite SERS substrate were examined using crystal violet (CV) and Rhodamine 6G (R6G) molecules, achieving a minimum detectable concentration of R6G at 10−9 M and the analytical enhancement factor (AEF) of 4.2 × 108. Moreover, SERS detection of biological samples with varying concentrations of Staphylococcus aureus demonstrated excellent biocompatibility of the SERS substrate and enabled quantitative analysis of bacterial concentration (R 2 = 99.7 %). Theoretical simulations using finite-difference time-domain (FDTD) analysis were conducted to examine the electromagnetic field distribution of the three-dimensional SERS composite substrate, confirming its local electric field enhancement effect. These experimental and theoretical results indicate that the Au@Ag NSs/PPSi substrate with a regulable pyramidal pitted array is a promising candidate for sensitive, label-free SERS detection in medical and biotechnological applications.

C21H18BrO3P, monoclinic, P21/c (no. 14), a = 20.2890(9) Å, b = 5.9736(2) Å, c = 16.1577(8) Å, β = 105.371(2)°, V = 1888.24(14) Å3, Z = 4, R gt(F) = 0.1359, wR ref(F 2) = 0.1414, T = 298.00 K.

Sophisticated infrared detection technology, operating through atmospheric transmission windows (usually between 3 and 5 μm and 8–13 μm), can detect an object by capturing its emitted thermal radiation, posing a threat to the survival of targeted objects. As per Wien’s displacement law, the shift of peak wavelength towards shorter wavelengths as blackbody temperature rises, underscores the significance of the 3–5 μm range for ultra-high temperature objects (e.g., at 400 °C), emphasizing the crucial need to control this radiation for the objects’ viability. Additionally, effective heat management is essential for ensuring the consistent operation of these ultrahot entities. In this study, based on a database with high-temperature resist materials, we introduced a material-informatics-based framework aimed at achieving the inverse design of simultaneous thermal camouflage (low emittance in the 3–5 μm range) and radiative cooling (high emittance in the non-atmospheric window 5–8 μm range) tailored for ultrahigh-temperature objects. Utilizing the transfer matrix method to calculate spectral properties and employing the particle swarm optimization algorithm, two optimized multilayer structures with desired spectral characteristics are obtained. The resulted structures demonstrate effective infrared camouflage at temperatures up to 250 °C and 500 °C, achieving reductions of 86.7 % and 63.7 % in the infrared signal, respectively. At equivalent heating power densities applied to the structure and aluminum, structure 1 demonstrates a temperature reduction of 29.4 °C at 0.75 W/cm2, while structure 2 attains a temperature reduction of 57.5 °C at 1.50 W/cm2 compared to aluminum, showcasing enhanced radiative cooling effects. This approach paves the way for attenuating infrared signals from ultrahigh-temperature objects and effectively managing their thermal conditions.

C19H18N2O, orthorhombic, Pna21 (no. 33), a = 21.838(2) Å, b = 13.9663(11) Å, c = 4.9806(4) Å, V = 1519.1(2) Å3, Z = 4, R gt(F) = 0.0702, wR ref(F 2) = 0.1948, T = 293 K.

Trapping and manipulating micro-objects and achieving high-precision measurements of tiny forces and displacements are of paramount importance in both physical and biological research. While conventional optical tweezers rely on tightly focused beams generated by bulky microscope systems, the emergence of flat lenses, particularly metalenses, has revolutionized miniature optical tweezers applications. In contrast to traditional objectives, the metalenses can be seamlessly integrated into sample chambers, facilitating flat-optics-based light manipulation. In this study, we propose an experimentally realized transmissive and polarization-insensitive water-immersion metalens, constructed using adaptive nano-antennas. This metalens boasts an ultra-high numerical aperture of 1.28 and achieves a remarkable focusing efficiency of approximately 50 % at a wavelength of 532 nm. Employing this metalens, we successfully demonstrate stable optical trapping, achieving lateral trapping stiffness exceeding 500 pN/(μm W). This stiffness magnitude aligns with that of conventional objectives and surpasses the performance of previously reported flat lenses. Furthermore, our bead steering experiment showcases a lateral manipulation range exceeding 2 μm, including a region of around 0.5 μm exhibiting minimal changes in stiffness for smoothly optical manipulation. We believe that this metalens paves the way for flat-optics-based optical tweezers, simplifying and enhancing optical trapping and manipulation processes, attributing ease of use, reliability, high performance, and compatibility with prevalent optical tweezers applications, including single-molecule and single-cell experiments.

The metasurface refractive index sensor has a high degree of tunability and flexibility, providing excellent performance for high precision refractive index sensing applications. The metasurface absorber with metallic structure has been hindered in further sensor applications due to the inherent Ohmic loss of the metallic material. In this study, a dual nanorod metasurface structure based on semiconductor Si was designed, introducing a symmetry-breaking structure to excite dual ultra-narrow q-BIC resonance peaks with Fano line shapes. Both peaks are located in the near-infrared region, and multipole analysis shows that this strong field enhancement effect is induced by a magnetic dipole. Experimental results demonstrate the potential of this sensor to provide dual-channel detection while achieving high sensitivity and high Q-factor. We believe that this device exhibits outstanding performance and high practicality, providing a reference for the development and application of biological and environmental sensors.

In this study, high-speed mid-infrared Mach–Zehnder electro-optical modulators in x-cut lithium niobate (LN) thin film on sapphire were designed, simulated, and analyzed. The main optical parameters of three types of Mach–Zehnder modulators (MZMs) (residual LN with thickness of 0, 0.5, and 1 μm) were simulated and calculated, namely, the single-mode conditions, bending loss, separation distance between electrode edge and lithium niobate waveguide edge, optical field distribution, and half-wave voltage–length product. The main radio frequency (RF) parameters of these three types of MZMs, such as characteristic impedance, attenuation constant, RF effective index, and the –3 dB modulation bandwidth were calculated depending on the dimensions of the coplanar waveguide traveling-wave electrodes. The modulations with residual LN thickness of 0, 0.5, and 1 μm were calculated with bandwidths exceeding 140, 150, and 240 GHz, respectively, and the half-wave voltage–length product achieved was 22.4, 21.6, and 15.1 V cm, respectively. By optimizing RF and optical parameters, guidelines for device design are presented, and the achievable modulation bandwidth is significantly increased.

Research is presented into the effect of density of Ge nanocrystals on violet-blue photoluminescence of Ge+-implanted SiO2 film.

Si-implanted thermal SiO2 films have two photoluminescence (PL) bands peaked at 4.3 eV and 2.4 eV respectively under -5 eV excitation. Following thermal annealing, the peak energy of the low-energy band moved from 2.4 eV to 2.7 eV, with annealing temperature rising to 1100 degrees C. The change of PL characteristics through annealing temperature is consistent with the recovery of the implantation-induced structure damage. The two PL bands could be due to neutral oxygen vacancies.

The effect of annealing on the electroluminescence (EL) was studied by examining the EL from Si+ implanted SiO2 prepared by thermal oxidation. The results were then compared with the photoluminescence to clarify its application in the study of Si-based visible light emitting materials. The results revealed that both EL and PL emanated from the same three luminescence bands around 470, 600 and 730 nm, with the 470 and 730 nm bands dominating the PL spectra in the samples annealed below and above 1000 degrees C, respectively.

The characteristics and mechanism of low-voltage-driven thin-film electroluminescent (TFEL) devices with low-resistivity ([10.sup.6]-[10.sup.7]-[Omega] cm) Si[O.sub.2]/[Ta.sub.2][O.sub.5] and [Al.sub.2][O.sub.3]/[Ta.sub.2][O.sub.5] stacked insulating films have been studied. At 50-Hz sinusoidal wave voltage excitation, the threshold voltage of devices with a ZnS:Mn emitting layer is below 40 V, and the brightness and luminous efficiency are above 1000 cd/[m.sup.2] and 4 lm/W, respectively, with 60 V voltage. The characteristics of brightness versus voltage (B-V) curves, integrated charge versus voltage (Q-V) figures, and luminous efficiency versus voltage ([Eta]-V) characteristics are different from conventional devices. The study of a special semiconductor layer-a thin probe-doped layer located at a different part of the pure ZnS layer-has proved that the excitation efficiency is not homogeneous across the emitting layer in this kind of device, and its value decreases from the anode toward the cathode, which is opposite of that made with TFEL devices with high-resistivity insulators. By offering a model of space-charge-limited current, the mechanism of low-voltage-driven thin-film electroluminescence, its optoelectronic characteristics, and the distribution characteristics of excitation efficiency across the emitting layer can be thoroughly explained. Key words: Thin film, electroluminescence, space-charge-limited current.

C22H14Cl2F4N2Pt, monoclinic, P21/n (no. 14), a = 16.858(9) Å, b = 14.876(8) Å, c = 17.125(9) Å, β = 98.552(6)°, V = 4247(4) Å3, Z = 8, Rgt(F) = 0.0337, wRref(F2) = 0.0778, T = 296 K.

Although traditional quantum-confined nanostructures e.g. regular quantum wells or quantum dots have achieved huge success in the field of semiconductor lasers for past decades, these traditional nanostructures are encountering the difficulty of enhancing device performance to a higher level due to their inherent gain bottleneck. In this paper, we are proposing a new super-gain nanostructure based on self-assembled well-wire complex energy-band engineering with InGaAs-based materials to break through the existing bottleneck. The nanostructure is constructed by utilizing the special strain-driven indium (In)-segregation and the growth orientation-dependent on-GaAs multi-atomic step effects to achieve the distinguished ultra-wide and uniform super-gain spectra. The structural details and its luminescence mechanism are investigated by multiple measurement means and theoretical modeling. The polarized gain spectra with the max fluctuation of

Two-dimensional electromagnetohydrodynamic behavior of nanofluids through rectangular microchannels is investigated. The combined effects of time-periodic pressure gradients and magnetic fields in terms of the Hall effects on nanofluid flow are considered. Under the Debye–Hückel linearization approximation, the semi-analytic solution of the velocity field is derived by Green’s function method. Furthermore, the semi-analytic solutions of electrokinetic energy conversion (EKEC) efficiency and the streaming potential of nanofluids through the rectangular microchannels are obtained. The variations of the velocity, streaming potential, and EKEC efficiency with the electric double layer thickness K, Hartmann number Ha, Hall parameter m, and dimensionless frequency Ω are shown and briefly discussed.

This study focuses on the research of spray-pump type unmanned surface vehicles (USVs). Based on the analysis of the dynamics and motion characteristics of USVs, a method combining Dubins curves and the particle swarm optimization algorithm is proposed to find the optimal or suboptimal solution for the formation path. The research goal is to switch multiple USVs from an unordered state to a formation state, taking the speed of USVs and the formation endpoint as dynamic variables and integrating Dubins curve theory into the particle swarm optimization algorithm. A theoretical framework for the formation of spray-pump type USVs is proposed. Finally, the formation of three USVs is realized in a simulation platform.

C13H13ClN2O3PtS, monoclinic, C2/c (no. 15), a = 7.9405(8) Å, b = 18.0744(18) Å, c = 21.513(2) Å, β = 98.781(1)∘, Z = 8, V = 3051.3(5) Å3, Rgt(F) = 0.0535, wRref(F2) = 0.0233, T = 296 K.

We present context-aware fidelity estimation (CAFE), a framework for benchmarking quantum operations that offers several practical advantages over existing methods such as randomized benchmarking (RB) and cross-entropy benchmarking. In CAFE, a gate or a subcircuit from some target experiment is repeated n times before being measured. By using a subcircuit, we account for effects from the spatial and temporal circuit context. Since coherent errors accumulate quadratically while incoherent errors grow linearly, we can separate them by fitting the measured fidelity as a function of n. One can additionally interleave the subcircuit with dynamical decoupling sequences to remove certain coherent error sources from the characterization when desired. We have used CAFE to experimentally validate our single- and two-qubit unitary characterizations by measuring fidelity against estimated unitaries. In numerical simulations, we find that CAFE produces fidelity estimates at least as accurate as interleaved RB while using significantly fewer resources. We also introduce a compact formulation for preparing an arbitrary two-qubit state with a single entangling operation and use it to present a concrete example using CAFE to study controlled-Z gates in parallel on a Sycamore processor.