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Block-coherence measures and coherence measures based on positive-operator-valued measures

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Communications in Theoretical physics 2022年第2期74卷 51-59页

作者： Liangxue Fu Fengli Yan Ting Gao college of physics Hebei Key Laboratory of Photophysics Research and ApplicationHebei Normal UniversityShijiazhuang 050024China School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024China

We study block-coherence measures based on the resource theory of block-coherence and coherence measures based on positive-operator-valued measures(POVM).Several blockcoherence measures are presented,including the block-coherence measure based on maximum relative entropy,the one-shot block-coherence cost under maximally block-incoherent operations,and the coherence measure based on coherent rank.Their relationships are obtained.Moreover,we describe the deterministic coherence dilution process by constructing blockincoherent operations.Based on the POVM coherence resource theory,we also propose two coherence measures and analyze their relationship.

关键词： coherence measure block-coherence measure positive-operator-valued measure

Propagation dynamics of dipole breathing wave in lossy nonlocal nonlinear media

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Chinese physics B 2022年第1期31卷 273-280页

作者：郭建丽杨振军李星亮张书敏 college of physics Hebei Key Laboratory of Photophysics Research and ApplicationHebei Normal UniversityShijiazhuang 050024China

In the framework of nonlinear wave optics,we report the evolution process of a dipole breathing wave in lossy nonlocal nonlinear media based on the nonlocal nonlinear Schrödinger equation.The analytical expression of the dipole breathing wave in such a nonlinear system is obtained by using the variational method.Taking advantage of the analytical expression,we analyze the influences of various physical parameters on the breathing wave propagation,including the propagation loss and the input power on the beam width,the beam intensity,and the wavefront curvature.Also,the corresponding analytical solutions are obtained.The validity of the analysis results is verified by numerical simulation.This study provides some new insights for investigating beam propagation in lossy nonlinear media.

关键词： breathing wave propagation variational method

Temporal and Spectral Characteristics of Persistent Emission and Special Bursts of Magnetar SGR J1935+2154 Based on Insight-HXMT

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research in Astronomy and Astrophysics 2024年第6期24卷 227-235页

作者： Xue-Feng Lu Li-Ming Song Ming-Yu Ge Shuang-Nan Zhang Jin-Lu Qu Ce Cai Cong-Zhan Liu Cheng-Kui Li Yu-Cong Fu Ying-Chen Xu key laboratory of Particle Astrophysics Institute of High Energy Physics University of Chinese Academy of Sciences Chinese Academy of Sciences College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal University Department of Astronomy Beijing Normal University

In October 2022, the magnetar SGR J1935+2154 entered the active outburst state. During the episode, the InsightHXMT satellite carried out a long observation that lasted for 20 days. More than 300 bursts were detected, and a certain amount of persistent radiation signals were also accumulated. This paper mainly introduces the results of persistent radiation profile folding and period search based on Insight-HXMT data. At the same time, the burst phase distribution characteristics, spectral lag results of burst, the spectral characteristics of zero-lag bursts and the time-resolved spectral evolution characteristics of high-flux bursts are reported. We found that there is no significant delay feature during different energy bands for the bursts of SGR J1935+2154. The observed zero-lag burst does not have a unique spectrum. The time-resolved spectrum of the individual burst has consistent spectral types and spectral parameters at different time periods of the burst. We also find that the burst number phase distribution and the burst photon phase distribution have the same tendency to concentrate in specific regions of the persistent emission profile.

关键词： dense matter magnetic fields radiation mechanisms: general

Structural transformation of metal–organic framework with constructed tetravalent nickel sites for efficient water oxidation

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Journal of Energy Chemistry 2022年第11期31卷 404-411,I0011页

作者： Weijian Wu Zhen Gao Qun Li Zhiya Wang Shiyin Liu Hongbo Wu Yuanchun Zhao Yalong Jiao Xiaojia Zhao hebei key laboratory of Inorganic Nano-materials College of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024HebeiChina hebei key laboratory of photophysics research and application College of PhysicsHebei Normal UniversityShijiazhuang 050024HebeiChina State key laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004HebeiChina

A mixture of Ni and Fe oxides is among the most commonly active catalysts for the oxygen evolution reaction(OER)during the water oxidation process.In particular,Ni oxide incorporated with even a small amount of Fe leads to substantively enhanced OER activity.However,the critical role of Fe species during the electrocatalytic process is still under evaluation.Herein,we report nickel(oxy)hydroxide incorporated with Fe through the surface reconstruction of a bimetallic metal-organic framework(NiFe-MOF)during the water oxidation process.The spectroscopic investigations with theoretical calculations reveal the critical role of Fe in promoting the formation of highly oxidized Ni^(4+),which directly correlates with an enhanced OER activity.Both the geometric and electronic structu res of the as-reconstructed Ni_(1-x)Fe_(x)OOH electrocatalysts can be delicately tuned by the Ni-Fe ratio of the bimetallic NiFe-MOF,further affecting the catalytic activity.As a result,the Ni_(1-x)Fe_(x)OOH derived from Ni_(0.9)Fe_(0.1)-MOF delivers low overpotentials of 260 mV at 10 mA cm^(-2)and 400 mV at 300 mA cm^(-2).

关键词： Structural transformation Bimetallic metal-organic framework Oxygen evolution reaction In-situ Raman spectroscopy High-valence metal sites

Topologically protected long-range coherent energy transfer

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Photonics research 2020年第11期8卷 I0050-I0057页

作者： Yujing Wang Jun Ren Weixuan Zhang Lu He Xiangdong Zhang key laboratory of Advanced Optoelectronic Quantum Architecture and Measurements of Ministry of Education School of PhysicsBeijing Institute of TechnologyBeijing 100081China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China

The realization of robust coherent energy transfer with a long range from a donor to an acceptor has many important applications in the field of quantum optics.However,it is hard to be realized using conventional schemes.Here,we demonstrate theoretically that robust energy transfer can be achieved using a photonic crystal platform,which includes the topologically protected edge state and zero-dimensional topological corner cavities.When the donor and the acceptor are put into a pair of separated topological cavities,the energy transfer between them can be fulfilled with the assistance of the topologically protected interface state.Such an energy transfer is robust against various kinds of defects,and can also occur over very long distances,which is very beneficial for biological detections,sensors,quantum information science,and so on.

关键词： protected topological transfer

Transformations of multilevel coherent states under coherence-preserving operations

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Science China(physics,Mechanics & Astronomy) 2021年第6期64卷 35-40页

作者： LiMei Zhang Ting Gao FengLi Yan School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024China Department of Mathematics and Computer Science Hengshui UniversityHengshui 053000China college of physics Hebei Key Laboratory of Photophysics Research and ApplicationHebei Normal UniversitsShijiazhuang 050024China

Quantum coherence,emerging from the"superposition"of quantum states,is widely used in various information processing tasks.Recently,the resource theory of multilevel quantum coherence is attracting substantial attention.In this paper,we mainly study the transformations of resource pure states via free operations in the theoretical framework for multilevel coherence.We prove that any two multilevel coherent resource pure states can be interconverted with a nonzero probability via a completely positive and trace non-increasing k-coherence-preserving map.Meanwhile,we present the condition of the interconversions of two multilevel coherent resource pure states under k-coherence-preserving operations.In addition,we obtain that in the resource-theoretic framework of multilevel coherence,no resource state is isolated,that is,given a multilevel coherent pure state|ψ>,there exists another multilevel coherent pure state|Φ>and a k-coherence-preserving operation∧k,such that∧k(|Φ>)=|ψ>.

关键词： multilevel coherent state k-coherence-preserving operation interconversion of two multilevel coherent resource pure states

Strong-field response time and its implications on attosecond measurement

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Chinese physics B 2022年第3期31卷 16-23页

作者：陈超车佳殷谢雪娇王赏辛国国陈彦军 college of physics and Information Technology Shaan'xi Normal UniversityXi'an 710119China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China School of physics Northwest UniversityXi'an 710127China

To measure and control the electron motion in atoms and molecules by the strong laser field on the attosecond time scale is one of the research frontiers of atomic and molecular photophysics. It involves many new phenomena and processes and raises a series of questions of concepts, theories, and methods. Recent studies show that the Coulomb potential can cause the ionization time lag(about 100 attoseconds) between instants of the field maximum and the ionization-rate maximum. This lag can be understood as the response time of the electronic wave function to the strong-field-induced ionization event. It has a profound influence on the subsequent ultrafast dynamics of the ionized electron and can significantly change the time–frequency properties of electron trajectory(an important theoretical tool for attosecond measurement). Here, the research progress of response time and its implications on attosecond measurement are briefly introduced.

关键词： response time strong-field ionization Coulomb effect attosecond measurement

Remote preparation for single-photon state in two degrees of freedom with hyper-entangled states

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Frontiers of physics 2021年第4期16卷 65-73页

作者： Mei-Yu Wang Fengli Yan Ting Gao college of physics Hebei Normal UniversityShijiazhuang 050024China School of Mathematics Science Hebei Normal UniversityShijiazhuang 050024China hebei key laboratory of photophysics research and application Shijiazhuang 050024China

Remote state preparation(RSP)provides a useful way of transferring quantum information between two distant nodes based on the previously shared entanglement.In this paper,we study RSP of an arbitrary single-photon state in two degrees of freedom(DoFs).Using hyper-entanglement as a shared resource,our first goal is to remotely prepare the single-photon state in polarization and frequency DoFs and the second one is to reconstruct the single-photon state in polarization and time-bin DoFs.In the RSP process,the sender will rotate the quantum state in each DoF of the photon according to the knowledge of the state to be communicated.By performing a projective measurement on the polarization of the sender’s photon,the original single-photon state in two DoFs can be remotely reconstructed at the receiver’s quantum systems.This work demonstrates a novel capability for longdistance quantum communication.

关键词： remote state preparation hyper-entanglement

构建准层状自空穴掺杂SnSe取向薄膜获得优异热电功率因子和输出功率密度

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Science Bulletin 2023年第22期68卷 2769-2778,M0005页

作者：薛宇利王晴高志钱鑫王江龙闫国英陈明敬赵立东王淑芳李志亮 hebei key laboratory of Optic-Electronic Information and Materials Key Laboratory of High-Precision Computation and Application of Quantum Field Theory of Hebei ProvinceCollege of Physics Science and TechnologyHebei UniversityBaoding 071002China School of Materials Science and Engineering Beihang UniversityBeijing 100191China Engineering research Center of Zero-Carbon Energy Buildings and Measurement Techniques Ministry of EducationHebei UniversityBaoding 071002China

热电技术可以实现热能与电能的相互转换,其开发利用对于缓解能源危机具有重要意义.近10年来,SnSe因其潜在的高能量转换效率、绿色环保和低成本特性而备受关注.但SnSe的固有载流子浓度低(约10~(17)cm^(-3)),导致其功率因子偏低,从而限制... 详细信息

热电技术可以实现热能与电能的相互转换,其开发利用对于缓解能源危机具有重要意义.近10年来,SnSe因其潜在的高能量转换效率、绿色环保和低成本特性而备受关注.但SnSe的固有载流子浓度低(约10~(17)cm^(-3)),导致其功率因子偏低,从而限制了SnSe基器件的输出功率密度.因此,探索新的载流子浓度优化策略对于SnSe的应用至关重要.此外,与三维块体相比,二维薄膜更易和现代半导体工艺相兼容,在热电微纳米器件的构筑和应用方面具有独特优势.本文报道了一种利用非原位硒化技术,通过电荷转移和自空穴掺杂效应来优化a轴取向SnSe基薄膜的载流子浓度.当硒化时间为20 min时,薄膜载流子浓度可提高至10~(18)cm^(-3)数量级,形成了准层状的自空穴掺杂SnSe基薄膜,其功率因子在600 K时达到了5.9μW cm^(-1)K^(-2).由硒化处理的SnSe基取向薄膜构筑的热电发电机在50和90 K的温差下分别具有约83、838μW cm^(-2)的超高功率密度.非原位硒化技术可以有效提高SnSe基薄膜的载流子浓度,为其他热电材料性能优化提供了一种新策略.

关键词： Thermoelectric property Thin film Tin selenide Post-selenization Carrier concentration