Converting beam polarizations into entanglement and classical correlation

The nonclassicality of a macroscopic single-mode optical superposition state is potentially convertible into entanglement, when the state is mixed with the vacuum on a beam splitter. Considering light beams with polarization degree of freedom in Euclidean space as coherent product states in a bipartite Hilbert space, we propose a method to convert the polarization amplitudes into entanglement and classical correlation through generating nonclassicality in the superpositions of coherent and displaced Fock states. Equivalent Bell state emerges from the resulted superpositions and the proportion of mixed entanglement and correlation, quantified by the metric pair of negativity and Schmidt number, is determined by the two displacements along the polarization directions. We further characterize the constructed states with Wigner functions and propose an experimental method for generating these states and measuring them via homodyne tomography

Deformation and fracture characteristics of ferrite/bainite dual-phase steels

The deformation and fracture characteristics of a low carbon Si&ndash;Mn steel with ferrite/bainite dual&ndash;phase structure were investigated by thermo&ndash;mechanical controlled process (TMCP). The results showed that the curves of the instantaneous work&ndash;hardening factor n* value versus true strain &epsilon; are made up with three stages during uniform plastic deformation: n* value is relatively higher at stage I, decreases slowly with &epsilon; in stage II, and then decreases quickly with &epsilon; in stage III. Compared tothe equiaxed ferrite/bainite dual&ndash;phase steel, the quasi&ndash;polygonal ferrite/bainite dual&ndash;phase steel shows higher tensile strength and n*value in the low strain region. The voids or micro&ndash;cracks formed not only at ferrite&ndash;bainite interfaces but also within ferrite grains in the necked region, which can improve the property of resistance to crack propagation by reducing local stress concentration of the crack tips.<br /

Dual polarization characteristics of an elevated thunderstorm hail event in the Nanling region

An elevated thunderstorm hail event occurred in Chenzhou and its vicinity in the Nanling region during March 22-23, 2023. A wide range of hail with diameters reaching up to 20 mm was reported, which was rare in elevated convection. In order to enhance the capability of forecasting and early warning of such hail events, this paper uses conventional meteorological observation data and SA-band dual-polarization radar products to analyze its weather conditions and dual-polarization radar echo characteristics. The results are as follows. (1) This event occurred in the cold area on the north side of the surface front, which was a typical elevated thunderstorm process. The hail-falling area was located 140 km to the north side of the surface front, and the large hail of 20 mm in diameter was caused by a supercell storm. (2) The storms that caused large hail in southern Chenzhou can be divided into four stages, which are the initial stage, the rapid development stage, the hail-falling stage, and the weakening stage. During the rapid development stage, the strong echo center increases rapidly and the vertical cumulative liquid water content (VIL) increases sharply. The differential reflectivity (ZDR) column extends to 4~5km above the 0 ℃ layer. A stronger updraft provides favorable conditions for hail development. During the hail-falling stage, with the rapid decrease of the strong echo center, the weak echo region (WER) disappears, and the height of the ZDR column decreases significantly. The values of ZDR and specific differential phase (KDP) gradually increase as the melting hail falls toward the ground. While the footprints of KDP correspond well with the hail-falling region. (3) The three-body scattering (TBSS) characteristics of large hail showed that the ZDR value at the root was large, which then decreased rapidly with the increase of radial distance, and the cross-correlation coefficient (CC) was significantly low. The sidelobal echo features of large hail indicate a low ZDR and low CC signature. These dual polarization features are key concerns for the large hail warning

Analysis of key warning points and environmental conditions for the '4.04'strong downburst event in Hengyang of Hunan

On the afternoon of 4 April, 2023, an intense downburst event (referred to as the '4.04' strong downburst) occurred in Hengyang, Hunan, causing serious disasters. This study analyzes the key warning indicators and environmental conditions for extreme strong winds using conventional meteorological observations, Doppler weather radar, and NCEP 1°×1° reanalysis data. The results are as follows: (1) The '4.04' strong downburst occurred under a 'baroclinic frontogenesis' weather system configuration, with a surface cold front providing the triggering conditions. The Skew-T plots clearly showed characteristics of high-level dryness and low-level moisture, unstable atmospheric convective parameters, and corrected convective available potential energy (CAPE), along with strong vertical wind shear, all conducive to the occurrence of extreme strong winds. (2) A mesoscale convective system (MCS) with bow echoes swept through Hengyang, causing regional downbursts. Extreme strong winds occurred when the corresponding storm cells moved rapidly, with maximum reflectivity factors reaching 60 dBz. The vertical integrated liquid water content and centroid height rapidly decreased. The reflectivity factors displayed a noticeable tilted structure, with clear features of bow echoes, rear-inflow jets, and radial velocity ambiguity. The low elevation asymmetric high-speed regions and velocity convergence are key warning indicators for extreme strong winds. (3) The strong downburst exhibited significant convective potential, with strong low-level moisture flux convergence and high specific humidity. There were conditions of thermal instability and vertical upward motion, along with low-level convergence and upper-level divergence. Cold air played an important role in the occurrence and development of this downburst event

Magnetic and transport properties of NiMnAl thin films

The magnetic and transport properties of Ni2MnAl thin films prepared using pulse laser deposition were investigated. It was shown that the films are granular and multiphase. Contrary to the data reported earlier we observe nonmonotonic temperature dependence of resistance with minimum in the vicinity of 100 K for the films deposited on substrates held at 773 K and negative magnetoresistance (MR) values of about 2.5% at 5 K and 1.6% at RT in magnetic field of 50 kOe. These values of MR are the highest reported up to date for Ni2MnAl films. Large negative MR in our films arises from a nonhomogeneous structure and its origin is the same as for granular films

Magnetic and transport properties of NiMnAl thin films

The magnetic and transport properties of Ni2MnAl thin films prepared using pulse laser deposition were investigated. It was shown that the films are granular and multiphase. Contrary to the data reported earlier we observe nonmonotonic temperature dependence of resistance with minimum in the vicinity of 100 K for the films deposited on substrates held at 773 K and negative magnetoresistance (MR) values of about 2.5% at 5 K and 1.6% at RT in magnetic field of 50 kOe. These values of MR are the highest reported up to date for Ni2MnAl films. Large negative MR in our films arises from a nonhomogeneous structure and its origin is the same as for granular films

The Effect of Spiritual Leadership on Employee Effectiveness: An Intrinsic Motivation Perspective

Drawing on spiritual leadership theory and intrinsic motivation theory, we proposed a homologous multilevel model to explore the effectiveness of spiritual leadership on employees’ task performance, knowledge sharing behaviors and innovation behaviors at the individual level. With questionnaires rated by 306 pairs of employees and their supervisors in 26 teams from the energy industry in mainland China, we conduct multilevel analysis to examine our hypotheses. The results show that spiritual leadership was positively related to employee task performance, knowledge sharing behaviors and innovation behavior, when we controlled for possible confounding effects of moral leadership and benevolent leadership, and ruled out alternative explanation of ethical leadership. The theoretical and practical implications are discussed

Staged characteristics analysis of a severe convection over the Dongting Lake area based on dual-polarization Doppler weather radar data

The multi-cell storm stage and squall line stage of a severe convective weather process over the Dongting Lake on 15 May 2021 in this study are analyzed mainly based on S-band dual-polarized doppler weather radar data. The study focuses on the analysis of the supercell storm I2 in the multi-cell storm stage. The results are as follows. (1) During the initial period of the I2, the strong echo area (the horizontal reflectivity factor, ZH > 55 dBz) and the differential reflectivity factor (ZDR) column (ZDR > 2.5 dB) extend to Wet Blub Zero (WBZ) level, corresponding to the areas with large specific differential phase (KDP) (> 1.7 °·km-1) and large correlation coefficient (CC) (0.9-0.99). It indicates that during this period, the precipitation phase is dominated by water condensate mingled with large raindrops, and these supercooled raindrops provide hail embryos for the later hail development. (2) During the hail colliding-growth period of the I2, ZH intensity and height increase rapidly, and vertically integrated liquid water content (VIL) shows an obvious leap increase. The strong-echo center (ZH > 60 dBz) extends to the level of above -10 ℃. In the corresponding regions, the ZDR drops below 0, the ZDR column (ZDR> 2.5 dB) extends to the level of -10 ℃, CC drops, and a "hole" appears in the KDP value area. These indicate that the precipitation during this period is dominated by solid particles and these solid particles are in an increasing period. (3) During the mature hailfall period of the I2, the bottom of the ZH intensity center (ZH > 60 dBz) drops below the WBZ level and the CC is locally as low as 0.8. There are ZDR negative areas and KDP voids in the corresponding area. These means that the dragging effect of the falling hail further weakens the strength of the updraft, which means that the hail is about to land. Then comes the squall line stage. (4) Unlike the multi-cell storm stage, the squall line stage has anomalously large KDP values and ZDR values greater than 1. (5) Before the occurrence of extreme gales of the squall line stage, the areas with strong echo greater than 55 dBz and velocity larger than 27 m·s-1 extend below 1 km, and the KDP in the strong echo area is obviously large, corresponding to the strong downdraft. Besides, the strong precipitation dragging effect caused by the melting of descending precipitation particles intensifies the generation of extreme gales