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Fast nuclear-spin gates and electrons−nuclei entanglement of neutral atoms in weak magnetic fields

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Frontiers of physics 2024年第2期19卷 179-203页

作者： xiao-feng Shi School of Physics Xidian UniversityXi’an 710071China

We present a novel class of Rydberg-mediated nuclear-spin entanglement in divalent atoms with global laser pulses.First,we show a fast nuclear-spin controlled phase gate of an arbitrary phase realizable either with two laser pulses when assisted by Stark shifts,or with three pulses.Second,we propose to create an electrons−nuclei-entangled state,which is named a super bell state(SBS)for it mimics a large Bell state incorporating three small Bell states.Third,we show a protocol to create a three-atom electrons-nuclei entangled state which contains the three-body W and Greenberger−Horne−Zeilinger(GHZ)states simultaneously.These protocols possess high intrinsic fidelities,do not require single-site Rydberg addressing,and can be executed with large Rydberg Rabi frequencies in a weak,Gauss-scale magnetic field.The latter two protocols can enable measurement-based preparation of Bell,hyperentangled,and GHZ states,and,specifically,SBS can enable quantum dense coding where one can share three classical bits of information by sending one particle.

关键词： nuclear-spin qubit electrons−nuclei entanglement super Bell state Greenberger−Horne−Zeilinger state Rydberg-mediated entanglement quantum dense coding

A Post-Quantum Cross-Domain Authentication Scheme Based on Multi-Chain Architecture

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Computers, Materials & Continua 2024年第2期78卷 2813-2827页

作者： Yi-bo Cao Xiu-bo Chen Yun-feng He Lu-Xi Liu Yin-Mei Che xiao Wang Ke xiao Gang Xu Si-Yi Chen Information Security Center State Key Laboratory ofNetworking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing100876China Information Center of China North Industries Group Corporation Beijing100089China School of Information Science and Technology North China University of TechnologyBeijing100144China

Due to the rapid advancements in network technology,blockchain is being employed for distributed data storage.In the Internet of Things(IoT)scenario,different participants manage multiple blockchains located in different trust domains,which has resulted in the extensive development of cross-domain authentication techniques.However,the emergence of many attackers equipped with quantum computers has the potential to launch quantum computing attacks against cross-domain authentication schemes based on traditional cryptography,posing a significant security threat.In response to the aforementioned challenges,our paper demonstrates a post-quantum cross-domain identity authentication scheme to negotiate the session key used in the cross-chain asset exchange process.Firstly,our paper designs the hiding and recovery process of user identity index based on lattice cryptography and introduces the identity-based signature from lattice to construct a post-quantum cross-domain authentication scheme.Secondly,our paper utilizes the hashed time-locked contract to achieves the cross-chain asset exchange of blockchain nodes in different trust domains.Furthermore,the security analysis reduces the security of the identity index and signature to Learning With Errors(LWE)and Short Integer Solution(SIS)assumption,respectively,indicating that our scheme has post-quantum security.Last but not least,through comparison analysis,we display that our scheme is efficient compared with the cross-domain authentication scheme based on traditional cryptography.

关键词： Cross-domain identity authentication lattice-based cryptography blockchain hashed time-locked contract

Intersection theory rules symbology

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 93-104页

作者： Jiaqi Chen bo feng Lilin Yang Beijing Computational Science Research Center Beijing 100084China Zhejiang Institute of Modern Physics School of PhysicsZhejiang UniversityHangzhou 310027China Peng Huanwu Center for Fundamental Theory Hefei 230026China

We propose a novel method to determine the structure of symbols for any family of polylogarithmic Feynman integrals.Using the d log-bases and simple formulas for the leading order and next-to-leading contributions to the intersection numbers,we give a streamlined procedure to compute the entries in the coefficient matrices of canonical differential equations,including the symbol letters and the rational coefficients.We also provide a selection rule to decide whether a given matrix element must be zero.The symbol letters are deeply related to the poles of the integrands and also have interesting connections to the geometry of Newton polytopes.Our method can be applied to many cutting-edge multi-loop calculations.The simplicity of our results also hints at the possible underlying structure in perturbative quantum field theories.

关键词： scattering amplitude Feynman integral symbology

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Efficient second and third harmonic generation in dual-layer lithium niobate microdisk resonator

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 33-38页

作者： Zhenzhong Hao xiao Wu Qiang Luo Zhang Li Rui Ma Fang bo feng Gao Guoquan Zhang Jingjun Xu MOE Key Laboratory of Weak-Light Nonlinear Photonics TEDA Institute of Applied Physics and School of PhysicsNankai UniversityTianjin 300457China

Lithium niobate thin film frequency doubler has extensive applications in the preparation of classical and quantum sources.In this study,we successfully fabricated microdisk resonators with a quality factor of 2.2×10^(5) in reverse-polarization dual-layer x-cut lithium niobate for the first time.Based on the modal phase matching condition,efficient second harmonic generation with a record normalized conversion efficiency of~56000%W-1 and cascaded third harmonic generation with an efficiency of~6500%W-2 were obtained in the microdisk resonator.Compared with the periodically poled lithium niobate microcavity,the complex domain structure preparation processes are avoided.Our work provides a scheme for achieving highly efficient second-order nonlinear effects in non-periodically poled microcavities.

关键词： harmonic lithium niobate

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Chronic pancreatitis:Pain and computed tomography/magnetic resonance imaging findings

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World Journal of Radiology 2024年第3期16卷 40-48页

作者： Yue feng Ling-Ji Song bo xiao Department of Radiology The Affilia Department of Radiology Bishan Hospital of Chongqing Medical UniversityBishan Hospital of ChongqingChongqing 402760China

Chronic pancreatitis(CP)is a fibroinflammatory disease characterized by irreversible destruction of pancreatic tissue.With the development of the disease,it may lead to exocrine and/or endocrine insufficiency.CP is one of the common diseases that cause abdominal pain,which will not get permanent spontaneous relief as the disease evolves.The American College of Gastroenterology clinical guidelines recommend computed tomography or magnetic resonance imaging as the first-line examination for the diagnosis of CP.CP common imaging findings include pancreatic atrophy,irregular dilatation of the pancreatic duct,calcification of pancreatic parenchyma,pancreatic duct stones,etc.In clinical practice,whether any correlations between CP-induced abdominal pain patterns(no pain/constant/intermittent pain)and corresponding imaging findings present are not well known.Therefore,this review aims to comprehensively sort out and analyze the relevant information by collecting lots of literature on this field,so as to construct a cross-bridge between the clinical manifestations and imaging manifestations of CP patients.Also,it provides an imaging basis and foundation for the classification and diagnosis of abdominal pain types in clinical CP patients.

关键词： Chronic pancreatitis Pancreatitis Abdominal pain Computed tomography Magnetic resonance imaging

Main controlling factor and mechanism of gas-in-place content of the Lower Cambrian shale from different sedimentary facies in the western Hubei area, South China

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Petroleum Science 2024年第3期21卷 1488-1507页

作者： Gang Li Xian-Ming xiao bo-Wei Cheng Chen-Gang Lu Yue feng Dong-Sheng Li School of Energy Resources China University of Geosciences (Beijing) Frontiers Science Center for Deep-time Digital Earth China University of Geosciences (Beijing)

The Lower Cambrian shale gas in the western Hubei area, South China has a great resource prospect, but the gas-in-place（GIP） content in different sedimentary facies varies widely, and the relevant mechanism has been not well understood. In the present study, two sets of the Lower Cambrian shale samples from the Wells YD4 and YD5 in the western Hubei area, representing the deep-water shelf facies and shallowwater platform facies, respectively, were investigated on the differences of pore types, pore structure and methane adsorption capacity between them, and the main controlling factor and mechanism of their methane adsorption capacities and GIP contents were discussed. The results show that the organic matter（OM） pores in the YD4 shale samples are dominant, while the inorganic mineral（IM） pores in the YD5 shale samples are primary, with underdeveloped OM pores. The pore specific surface area（SSA） and pore volume（PV） of the YD4 shale samples are mainly from micropores and mesopores, respectively,while those of the YD5 shale samples are mainly from micropores and macropores, respectively. The methane adsorption capacity of the YD4 shale samples is significantly higher than that of the YD5 shale samples, with a maximum absolute adsorption capacity of 3.13 cm3/g and 1.31 cm3/g in average,respectively. Compared with the shallow-water platform shale, the deep-water shelf shale has a higher TOC content, a better kerogen type and more developed OM pores, which is the main mechanism for its higher adsorption capacity. The GIP content models based on two samples with a similar TOC content selected respectively from the Wells YD4 and YD5 further indicate that the GIP content of the deep-water shelf shale is mainly 3 4 m3/t within a depth range of 1000—4000 m, with shale gas exploration and development potential, while the shallow-water platform shale has normally a GIP content of <1 m3/t,with little shale gas potential. Considering the geological and geochemical conditions of shale gas formation and preservation, the deep-w

关键词： Lower Cambrian shale Deep-water shelf facies Shallow-water platform facies Pore structure Methane adsorption Gas-in-place content Controlling factor

Severe liver injury and clinical characteristics of occupational exposure to 2-amino-5-chloro-N,3-dimethylbenzamide: A case series

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 186-194页

作者： Meng-xiao feng Hua Zou Yuan-Qiang Lu Department of Emergency Medicine The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Key Laboratory for Diagnosis and Treatment of Aging and Physic-chemical Injury Diseases of Zhejiang Province Hangzhou 310003China Occupational Health and Radiation Protection Institute Zhejiang Provincial Center for Disease Control and PreventionHangzhou 310051China

Background:The 2-amino-5-chloro-N,3-dimethylbenzamide is a key intermediate in the synthesis of pesticides and pharmaceuticals.However,no literature currently exists on 2-amino-5-chloro-N,3-dimethylbenzamide poisoning in humans.This study aimed to reveal the health hazard of this chemical for humans and summarize the clinical characteristics of patients with occupational 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.Methods:This observational study included four patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning from June 2022 to July 2022.The entire course of the incidents was described in detail.Blood 2-amino-5-chloro-N,3-dimethylbenzamide concentrations were detected by a mass spectrometer.Hema-toxylin and eosin staining was performed to assess liver injury,and immunofluorescence was used to evaluate hepatic mitophagy.Results:The 2-amino-5-chloro-N,3-dimethylbenzamide powder(99%purity)entered the human body mainly via the skin and respiratory tract due to poor personal protective measures.The typical course of 2-amino-5-chloro-N,3-dimethylbenzamide poisoning was divided into latency,rash,fever,organic dam-age,and recovery phases in accordance with the clinical evolution.Rash and fever may be the important premonitory symptoms for further organ injuries.The chemical was detected in the blood of all patients and caused multiple organ injuries,predominantly liver injury,including kidney,myocardium,and micro-circulation.Three patients recovered smoothly after comprehensive treatments,including artificial liver therapy,continuous renal replacement therapy,glucocorticoids,and other symptomatic and supportive treatments.One patient survived by liver transplantation.The postoperative pathological findings of the removed liver showed acute liver failure,and immunofluorescence staining confirmed the abundance of mitophagy in residual hepatocytes.Conclusions:This study is the first to elaborate the clinical characteristics of patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.The chemical enter

关键词： 2-amino-5-chloro-N,3-dimethylbenzamide Poisoning Clinical characteristics Liver injury

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A Trust Evaluation Mechanism Based on Autoencoder Clustering Algorithm for Edge Device Access of IoT

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Computers, Materials & Continua 2024年第2期78卷 1881-1895页

作者： xiao feng Zheng Yuan Cyber Security Academy Beijing University of Posts and TelecommunicationsBeijing100876China Department of Cyberspace Security Beijing Electronic Science and Technology InstituteBeijing100070China State Grid Info-Telecom Great Power Science and Technology Co. Ltd.Beijing102211China

First,we propose a cross-domain authentication architecture based on trust evaluation mechanism,including registration,certificate issuance,and cross-domain authentication processes.A direct trust evaluation mechanism based on the time decay factor is proposed,taking into account the influence of historical interaction records.We weight the time attenuation factor to each historical interaction record for updating and got the new historical record data.We refer to the beta distribution to enhance the flexibility and adaptability of the direct trust assessment model to better capture time trends in the historical record.Then we propose an autoencoder-based trust clustering algorithm.We perform feature extraction based on autoencoders.Kullback leibler(KL)divergence is used to calculate the reconstruction error.When constructing a convolutional autoencoder,we introduce convolutional neural networks to improve training efficiency and introduce sparse constraints into the hidden layer of the autoencoder.The sparse penalty term in the loss function measures the difference through the KL divergence.Trust clustering is performed based on the density based spatial clustering of applications with noise(DBSCAN)clustering algorithm.During the clustering process,edge nodes have a variety of trustworthy attribute characteristics.We assign different attribute weights according to the relative importance of each attribute in the clustering process,and a larger weight means that the attribute occupies a greater weight in the calculation of distance.Finally,we introduced adaptive weights to calculate comprehensive trust evaluation.Simulation experiments prove that our trust evaluation mechanism has excellent reliability and accuracy.

关键词： Cross-domain authentication trust evaluation autoencoder

Pressure-induced emission(PIE)in halide perovskites toward promising applications in scintillators and solid-state lighting

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Aggregate 2024年第1期5卷 9-15页

作者： Wenya Zhao Guanjun xiao bo Zou State Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchunChina

High-pressure chemistry has provided a huge boost to the development of scientific community.Pressure-induced emission(PIE)in halide perovskites is gradually showing its unique charm in both pressure sensing and optoelectronic device applications.Moreover,the PIE retention of halide perovskites under ambient conditions is of great commercial value.Herein,we mainly focus on the potential applications of PIE and PIE retention in metal halide perovskites for scintillators and solid-state lighting.Based on the performance requirements of scintillator and single-component white light-emitting diodes(WLEDs),the significance of PIE and PIE retention is critically clarified,aiming to design and synthesize materials used for high-performance optoelectronic devices.This perspective not only demonstrates promising applications of PIE in the fields of scintillators and WLEDs,but also provides potential applications in display imaging and anti-counterfeiting of PIE materials.Furthermore,solving the scientific disputes that exist under ambient conditions is also simply discussed as an outlook by introducing high-pressure dimension to produce PIE.

关键词： halide perovskites high pressure light-emitting diode pressure-induced emission scintillators solidstate lighting