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<jats:title>Abstract</jats:title> <jats:p>Understanding the relation between spatial heterogeneity and structural rejuvenation is one of the hottest topics in the field of metallic glasses (MGs). In this work, molecular dynamics (MD) simulation was implemented to discover the effects of initial spatial heterogeneity on the level of rejuvenation in the Ni<jats:sub>80</jats:sub>P<jats:sub>20</jats:sub> MGs. For this purpose, the samples were prepared with cooling rates of 10<jats:sup>10</jats:sup>-10<jats:sup>12</jats:sup> K/s to make glassy alloys with different atomic configurations. Firstly, it was found that the increase in the cooling rate leads to the widening of Gaussian-type shear modulus distribution, indicating the aggregation in both elastically soft and hard regions. After the primary evaluations, the elastostatic loading was also applied to induce structural rejuvenation into the atomic configurations. The results indicated that the sample with intermediate structural heterogeneity, i.e. prepared with 10<jats:sup>11</jats:sup> K/s, exhibited the maximum structural rejuvenation. This event is due to the fact that the atomic configuration in an intermediate structure contains more potential sites for generating the maximum atomic rearrangement and loosely packed regions under an external excitation. The features of atomic rearrangement and structural changes under the rejuvenation process are discussed in details.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>A novel design method of chalcogenide long-period fiber grating (LPFG) sensor based on the dual-peak resonance effect of LPFG near the phase matching turning point (PMTP) is presented. The refractive index sensing in high refractive index chalcogenide fiber was achieved by a coated thin-cladding film. The dual-peak resonant characteristics near PMTP and refractive index sensing properties of LPFG are analyzed first by the phase-matching condition of LPFG. The effects of film parameters and cladding radius on the sensitivity of refractive index are further discussed. The sensor is optimized by selecting appropriate film parameters and cladding radius. Simulation results show that the ambient refractive index sensitivity of dual-peak coated thin-cladding chalcogenide LPFG at the PMTP can be 2400 nm/RIU, which is significantly higher than that of non-optimized gratings. It has great application potential in the field of chemical and biosensor.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We report an experimental demonstration of geopotential difference measurement using a pair of transportable <jats:sup>40</jats:sup>Ca<jats:sup>+</jats:sup> optical clocks (TOC-729-1 and TOC-729-3) in the laboratory, each of them with an uncertainty of 1.3 × 10<jats:sup>-17</jats:sup> and an instability of 4.8 × 10<jats:sup>-15</jats:sup>/ √ τ, respectively. Referenced to a stationary clock of TOC-729-1, geopotential difference measurements are realized by moving TOC-729-3 to three different locations and the relevant altitude differences are measured with uncertainties at the level of 20 cm. After correcting the systematic shifts (including gravitational red shift), these two-clock frequency difference is measured to be -0.7(2.2) × 10<jats:sup>-17</jats:sup>, considering both the statistic (1.0 × 10<jats:sup>-17</jats:sup>) and the systematic (1.9 × 10<jats:sup>-17</jats:sup>) uncertainty. The frequency difference between these two clocks is within their respective uncertainties, verifying the reliability of transportable <jats:sup>40</jats:sup>Ca<jats:sup>+</jats:sup> optical clocks at the low level of 10<jats:sup>-17</jats:sup>.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>To describe the dynamic response characteristics of the laminated graded-bandgap GaAs-based photocathode with distributed Bragg reflection structure, a general theoretical temporal response model is deduced combining the unsteady continuity equation and numerical calculation method. Through the model, the contribution of the distribution Bragg reflection structure and graded-bandgap emission layer to the temporal response is investigated separately. Meanwhile, the relationships between the temporal response characteristics of the laminated GaAs-based photocathode and different structural parameters are also analyzed, including average electron decay time, emission layer thickness and incident light wavelength. It is found that the introduction of DBR layer resolves the contradiction between the absorption ability of the emission layer and the temporal response. Moreover, the distributed Bragg reflection layer has the effect of improving the time response by optimizing the initial photoelectron distribution. The improvement effect of the distribution Bragg reflection layer on the temporal response is enhanced with the decrease of the emission layer thickness or the increase of the incident light wavelength. These results explain the effect of the distribution Bragg reflection layer of the photocathode on the dynamic characteristics, which can offer new insights into the dynamic research of GaAs-based photocathode.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>PbF, a valuable candidate for the measurement of the electron electric dipole moment (eEDM), is of great significance to measure its spectrum and derive its molecular constants in experiment. In the present work, the rovibronic spectrum of the <jats:italic>B</jats:italic> <jats:sup>2</jats:sup>Σ<jats:sup>+</jats:sup> - <jats:italic>X</jats:italic> <jats:sub>1</jats:sub> <jats:sup>2</jats:sup>Π<jats:sub>1/2</jats:sub> transition of PbF in the range of 260-285 nm has been studied using laser ablation/laser induced fluorescence method. The molecular parameters of the <jats:italic>X</jats:italic> <jats:sub>1</jats:sub> <jats:sup>2</jats:sup>Π<jats:sub>1/2</jats:sub>(v" = 0) and <jats:italic>B</jats:italic> <jats:sup>2</jats:sup>Σ<jats:sup>+</jats:sup> (v' = 0, 1) states were derived from the recorded spectra of the (0, 0) and (1, 0) bands of the <jats:italic>B</jats:italic> <jats:sup>2</jats:sup>Σ<jats:sup>+</jats:sup> - <jats:italic>X</jats:italic> <jats:sub>1</jats:sub> <jats:sup>2</jats:sup>Π<jats:sub>1/2</jats:sub> transition. Also, the Franck-Condon factors (FCFs) of the transitions between the <jats:italic>B</jats:italic> <jats:sup>2</jats:sup>Σ<jats:sup>+</jats:sup> and <jats:italic>X</jats:italic> <jats:sub>1</jats:sub> <jats:sup>2</jats:sup>Π<jats:sub>1/2</jats:sub> states were calculated using the RKR/LEVEL and Morse potential methods, respectively.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The two types of nonlinear optical cryptosystems (NOCs) that are respectively based on amplitude-phase retrieval algorithm (APRA) and phase retrieval algorithm (PRA) have attracted a lot of attention due to their unique mechanism of encryption process and remarkable ability to resist common attacks. In this paper, for the first time, to the best of our knowledge, the security of the two types NOCs is evaluated by using a deep-learning (DL) method, wherein an end-to-end densely connected convolutional network (DenseNet) model for cryptanalysis is developed. The proposed DL-based method is able to retrieve unknown plaintexts from the given ciphertexts by using the trained DenseNet model without a prior knowledge of any public or private keys. The results of numerical experiments with the DenseNet model clearly demonstrate the validity and good performance of the proposed the DL-based attack on NOCs.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>A monoclinic <jats:italic>α</jats:italic>-MoP<jats:sub>2</jats:sub>, with the OsGe<jats:sub>2</jats:sub>-type structure (space group: <jats:italic>C</jats:italic>2/<jats:italic>m</jats:italic>, <jats:italic>Z</jats:italic> = 4) and lattice parameters <jats:italic>a</jats:italic> = 8.7248(11) Å, <jats:italic>b</jats:italic> = 3.2322(4) Å, <jats:italic>c</jats:italic> = 7.4724(9) Å, and <jats:italic>β</jats:italic> = 119.263°, was synthesized under a pressure of 4 GPa and at the temperature between 1100 ℃ and 1200 ℃ . The structure of <jats:italic>α</jats:italic>-MoP<jats:sub>2</jats:sub> and its relation with other transition metal diphosphides are discussed. Surprisingly, the ambient pressure phase orthorhombic <jats:italic>β</jats:italic>-MoP<jats:sub>2</jats:sub> (space group: <jats:italic>Cmc</jats:italic>2<jats:sub>1</jats:sub>) is denser in structure than that of <jats:italic>α</jats:italic>-MoP<jats:sub>2</jats:sub>. Room temperature high-pressure X-ray diffraction studies exclude the possibility for phase transition from the <jats:italic>β</jats:italic>-MoP<jats:sub>2</jats:sub> to <jats:italic>α</jats:italic>-MoP<jats:sub>2</jats:sub>, suggesting that the <jats:italic>α</jats:italic>-MoP<jats:sub>2</jats:sub> is a stable phase at ambient conditions, which is also supported by the total energy and phonon calculations.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In this paper, we discover a phenomenon of inhibition effect induced by fractional Gaussian noise in Neuronal System. First, essential properties of fractional Brownian motion(fBm) and generation of fractional Gaussian noise(fGn) are presented, and representative sample paths of fBm and corresponding spectral density of fGn are discussed at different Hurst indexes. Next, we consider the effect of fGn on neuronal firing, and observe that neuronal firing decreases first and then increases with increasing noise intensity and Hurst index of fGn by studying time series evolution. To further quantify inhibitory effect of fGn, by introducing average discharge rate, we investigate the effects of noise and external current on neuronal firing, and find the occurrence of inhibitory effect about noise intensity and Hurst index of fGn at a certain level of current. Moreover, inhibition effect is not easy to occur when noise intensity and Hurst index are too large or too small. In view of opposite action mechanism compared with stochastic resonance, this suppression phenomenon is called inverse stochastic resonance(ISR). Finally, the inhibitory effect induced by fGn is further verified based on the inter-spike intervals(ISIs) in neuronal system. Our work lays a solid foundation for future study of non-Gaussian-type noise on neuronal systems.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We report the temperature dependence of the spin pumping effect for Y<jats:sub>3</jats:sub>Fe<jats:sub>5</jats:sub>O<jats:sub>12</jats:sub> (YIG, 0.9 μm)/NiO (<jats:italic>t</jats:italic> <jats:sub>NiO</jats:sub> nm)/W (6 nm) (<jats:italic>t</jats:italic> <jats:sub>NiO</jats:sub> = 0, 1, 2, 10 nm) heterostructures. All samples exhibit a strong temperature-dependent the inverse spin Hall effect (ISHE) signal <jats:italic>I</jats:italic> <jats:sub>c</jats:sub> and sensitivity to the NiO layer thickness. We observe a dramatic decrease of <jats:italic>I</jats:italic> <jats:sub>c</jats:sub> with inserting thin NiO layer between YIG and W layers indicating that the inserting NiO layer significantly suppresses the spin transport from YIG to W. In contrast to noticeable enhancement in YIG/NiO (<jats:italic>t</jats:italic> <jats:sub>NiO</jats:sub> ≈ 1-2 nm)/Pt, the suppression of spin transport may be closely related to the specific interface-dependent spin scattering, spin memory loss, and spin conductance at the NiO/W interface. Besides, the <jats:italic>I</jats:italic> <jats:sub>c</jats:sub> of YIG/NiO/W exhibits a maximum near the <jats:italic>T</jats:italic> <jats:sub>N</jats:sub> of the AF NiO layer, which is due to the spins are transported dominantly by incoherent thermal magnons.</jats:p>

<jats:p>The anti-trigonometric function is used to strictly solve the uniaxial anisotropic Stoner–Wohlfarth (SW) model, which can obtain the relation of the angle <jats:italic>α</jats:italic>(<jats:italic>θ</jats:italic>) between the magnetization (the anisotropy field) and the applied magnetic field. Using this analytic solution, the hysteresis loops of uniaxial anisotropic SW particles magnetized in typical directions could be numerically calculated. Then, the hysteresis loops are obtained in randomly distributed SW particle ensembles while ignoring the dipole interaction among them with the analytic solution. Finally, the correctness of the analytic solution is verified by the exact solutions of remanence, switching field, and coercivity from the SW model. The analytic solution provides an important reference for understanding the magnetizing and magnetization reversal processes of magnetic materials.</jats:p>