High-efficiency multipartite entanglement purification of electron-spin states with charge detection

We present a high-efficiency multipartite entanglement purification protocol (MEPP) for electron-spin systems in a Greenberger–Horne–Zeilinger state based on their spins and their charges. Our MEPP contains two parts. The first part is our normal MEPP with which the parties can obtain a high-fidelity N-electron ensemble directly, similar to the MEPP with controlled-not gates. The second one is our recycling MEPP with entanglement link from N′-electron subsystems (2 < N′ < N). It is interesting to show that the N′-electron subsystems can be obtained efficiently by measuring the electrons with potential bit-flip errors from the instances which are useless and are just discarded in all existing conventional MEPPs. Combining these two parts, our MEPP has the advantage of the efficiency higher than other MEPPs largely for electron-spin systems.     

Theoretical calculation and evaluation of n +~(240,242,244)Pu reactions

The nuclear data of n+~(240;242;244)Pu reactions for incident energy below 200 MeV are calculated and evaluated to meet the requirement in the design of an accelerator-driven subcritical system. The optical model is used to calculate the total, nonelastic, shape elastic cross sections, shape elastic scattering angular distributions, and transmission coefficients. The distorted-wave Born approximation is applied to calculate the direct inelastic scatterings to the discrete excited states. The nuclear reaction statistical models and fission theory are applied to describe neutron, proton, deuteron, triton, helium-3, alpha and c emissions, and fission consistently. The results thus obtained are compared with experimental data and the evaluated data obtained from ENDF/B-VII.1 and JENDL-4.0.     

基于高光谱成像的主成分分析和波谱角分类技术的天麻粉质量标志物及相关成分可视化快速检测

目的 利用高光谱成像(hyperspectral imaging, HSI)技术, 通过一种原位质量标志物评估方法, 与高效液相色谱含量测定相结合, 建立预测模型对不同来源的天麻粉进行可视化评价。方法 采用高效液相色谱法(high performance liquid chromatography, HPLC)测定不同产地、不同晾干方式天麻粉中6种质量标志物含量并作为金标准; 苯酚-硫酸法测定天麻多糖含量、水分测定仪测定含水量, 两者作为辅助评价指标。HSI选用可见近红外(visible near-infrared, VNIR)和短波红外(short wave infrared, SWIR)双波段光谱进行分析比较。结果 以鲜品切块晾干方式制备的天麻粉的质量标志物对羟基苯甲醇、多糖和水分含量均增加, 同时天麻素和巴利森苷含量显著减少甚至消失。根据高光谱图像主成分分析(principal component analysis, PCA)预处理特征, 基于波谱角(spectral angle mapper, SAM)的监督分类算法对不同产地和加工方式制备的天麻粉进行了原位、无损分类, 其建立的线性回归模型实现了质量标志物含量的反演预测。结论 通过高效液相色谱含量测定的准确性和高光谱原位预测的无损性相结合的方式进行现场可视化评价和预测, 可以为不同产地、不同加工方式的天麻粉质量标志物快速检测提供技术参考。     

Development and Property Tuning of Refractory High-Entropy Alloys: A Review

In the past decade, multi-principal element high-entropy alloys (referred to as high-entropy alloys, HEAs) are an emerging alloy material, which has been developed rapidly and has become a research hotspot in the fi eld of metal materials. It breaks the alloy design concept of one or two principal elements in traditional alloys. It is composed of fi ve or more principal elements, and the atomic percentage (at.%) of each element is greater than 5%but not more than 35%. The high-entropy eff ect ca...     

Bell-state generation on remote superconducting qubits with dark photons

We present a scheme to generate the Bell state deterministically on remote transmon qubits coupled to different 1D superconducting resonators connected by a long superconducting transmission line. Using the coherent evolution of the entire system in the all-resonance regime, the transmission line need not to be populated with microwave photons which can robust against the long transmission line loss. This lets the scheme more applicable to the distributed quantum computing on superconducting quantum circuit. Besides, the influence from the small anharmonicity of the energy levels of the transmon qubits can be ignored safely.     

Correlation dynamics of a two-qubit system in a Bell-diagonal state under non-identical local noises

The property of quantum correlation has been studied in recent years, especially for the quantum and classical correlations affected by environment. The dynamics of quantum and classical correlations in two-qubit system under identical local noise channels have been investigated recently. Here, we will consider the dynamics of quantum and classical correlations when the local noise channels of two sides are not identical. We investigate the dynamics of quantum and classical correlations with three types of local noise channels in both Markovian and non-Markovian conditions and show the decay rules of quantum and classical correlations with different types and parameter times of local noise channels.     

Optimal multipartite entanglement concentration of electron-spin states based on charge detection and projection measurements

We propose an optimal entanglement concentration protocol (ECP) for nonlocal $N$ -electron systems in a partially entangled Greenberger–Horne–Zeilinger (GHZ) pure state, resorting to charge detection and the projection measurement on an additional electron. For each nonlocal $N$ -electron system in a partially entangled GHZ state, one party in quantum communication, say Alice first entangles it with an additional electron, and then, she projects the additional electron into an orthogonal basis for dividing the $N$ -electron systems into two groups. In the first group, the $N$ parties obtain a subset of $N$ -electron systems in a maximally entangled state directly. In the second group, they obtain some less-entangled $N$ -electron systems which are the resource for the entanglement concentration in the next round. By iterating the entanglement concentration process several times, the present ECP has the maximal success probability, the theoretical limit of an ECP as it just equals to the entanglement of the partially entangled state, far higher than others. Moreover, this ECP for an $N$ -electron GHZ-type state requires only one additional electron, not two or more, and it does not resort to a collective unitary evolution, far different from others, which may decrease the difficulty for its implementation in experiment. When it is used for an $N$ -electron W-type state, $N-1$ additional electrons are required only.     

热处理对鲜切牛蒡贮藏品质的影响

目的采用星点设计-响应面法研究了热处理对鲜切牛蒡贮藏品质的影响。方法对鲜切牛蒡进行不同时间和不同温度的热处理,处理后的牛蒡切片置于23℃±2℃条件下5 d(模拟货架期),对货架结束后的牛蒡色泽L*值、失重率和维生素C(VC)含量进行测定。采用响应面法建立了牛蒡色泽L*值、失重率和VC含量的二次多项数学模型,并验证了模型的有效性。结果热处理鲜切牛蒡的最佳处理温度为46.5℃,处理时间28.8min,在此条件下,牛蒡色泽L*值、失重率和VC含量理论值分别为66.07、0.78%和6.16 mg/100 g。实际测得L*值66.13±1.7,失重率(0.79±0.03)%,VC含量(6.12±0.12)mg/100 g,与预测值基本一致,表明所建模型具有较好的预测性能,可用于指导生产实践。结论热处理可有效降低鲜切牛蒡贮藏品质的下降。     

Projectile fragment emission in the fragmentation of $$^{\bf 56}\mathbf{Fe}$$ on Al,C, and $$\mathbf{CH}_{\mathbf{2}}$$ targets

There are two infrared beamlines at the Shanghai synchrotron radiation facility (SSRF)-BL01B and BL06B.BL01B was the first infrared beamline of the National Facility for Protein Science in Shanghai at SSRF,which is dedicated to synchrotron infrared micro spectroscopy.It utilizes bending magnet radiation and edge radiation as light sources.Diffraction-limited spatial resolution is reached in the infrared microspectroscopy experiment.BL01B has been in operation for approximately five years since it opened in January 2015.In the past few years,many meaningful results have been published by user groups from various disciplines,such as biomacromolecule materials and pharmaceutical,environmental,and biomedical sciences.In addition,a new infraredbeamline station BL06B is under construction,which is optimized for the mid-infrared and far-infrared band.BL06B is equipped with a vacuum-type Fourier transform infrared spectrometer,infrared microscope,custom longworking-distance infrared microscope,infrared scanning near-field optical microscope,and mid-infrared Mueller ellipsometer.The purpose is to serve experiments with high vacuum requirements and spatial resolution experiments,as well as those that are in situ and time-sensitive,such as high-pressure and atomic force microscopy infrared experiments.The station can be used for research in biomaterials,pharmacy,geophysics,nanotechnology,and semiconductor materials.