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Near-term quantum computing techniques: Variational quantum algorithms, error mitigation, circuit compilation, benchmarking and classical simulation

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Science China(Physics,Mechanics & Astronomy) 2023年第5期66卷 23-72页

作者： He-Liang Huang Xiao-Yue Xu Chu guo guojing Tian Shi-Jie wei Xiaoming Sun Wan-Su bao gui-Lu long Henan Key Laboratory of Quantum Information and Cryptography Zhengzhou 450000China State Key Lab of Processors Institute of Computing TechnologyChinese Academy of SciencesBeijing 100190China School of Computer Science and Technology University of Chinese Academy of SciencesBeijing 100049China Beijing Academy of Quantum Information Sciences Beijing 100193China Department of Physics Tsinghua UniversityBeijing 100084China

Quantum computing is a game-changing technology for global academia,research centers and industries including computational science,mathematics,finance,pharmaceutical,materials science,chemistry and *** it has seen a major boost in the last decade,we are still a long way from reaching the maturity of a full-fledged quantum *** said,we will be in the noisy-intermediate scale quantum(NISQ)era for a long time,working on dozens or even thousands of qubits quantum computing *** outstanding challenge,then,is to come up with an application that can reliably carry out a nontrivial task of interest on the near-term quantum devices with non-negligible quantum *** address this challenge,several near-term quantum computing techniques,including variational quantum algorithms,error mitigation,quantum circuit compilation and benchmarking protocols,have been proposed to characterize and mitigate errors,and to implement algorithms with a certain resistance to noise,so as to enhance the capabilities of near-term quantum devices and explore the boundaries of their ability to realize useful ***,the development of near-term quantum devices is inseparable from the efficient classical sim-ulation,which plays a vital role in quantum algorithm design and verification,error-tolerant verification and other *** review will provide a thorough introduction of these near-term quantum computing techniques,report on their progress,and finally discuss the future prospect of these techniques,which we hope will motivate researchers to undertake additional studies in this field.

关键词： quantum computing noisy-intermediate scale quantum variational quantum algorithms error mitigation circuit com-pilation benchmarking protocols classical simulation

Modulating poststroke inflammatory mechanisms: Novel aspects of mesenchymal stem cells, extracellular vesicles and microglia

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World Journal of Stem Cells 2021年第8期13卷 1030-1048页

作者： Wen-Qiang Xin wei wei Yong-Li Pan bao-long Cui Xin-Yu Yang Mathias Bähr Thorsten R Doeppner Department of Neurology University Medical Center GöttingenGöttingen 37075Germany Department of Neurosurgery Tianjin Medical University General HospitalTianjin 300052China

Inflammation plays an important role in the pathological process of ischemic stroke,and systemic inflammation affects patient *** resident immune cells in the brain,microglia are significantly involved in immune defense and tissue repair under various pathological conditions,including cerebral *** the differentiation of M1 and M2 microglia is certainly oversimplified,changing the activation state of microglia appears to be an intriguing therapeutic strategy for cerebral *** evidence indicates that both mesenchymal stem cells(MSCs)and MSC-derived extracellular vesicles(EVs)regulate inflammation and modify tissue repair under preclinical stroke ***,the precise mechanisms of these signaling pathways,especially in the context of the mutual interaction between MSCs or MSC-derived EVs and resident microglia,have not been sufficiently ***,this review summarizes the state-ofthe-art knowledge on MSC-and MSC-EV-mediated regulation of microglial activity under ischemic stroke conditions with respect to various signaling pathways,including cytokines,neurotrophic factors,transcription factors,and microRNAs.

关键词： Extracellular vesicles Mesenchymal stem cells Microglial activation M2 polarization Ischemic stroke

Two-Mode Excited Squeezed Vacuum State and Its Properties

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Communications in Theoretical Physics 2008年第5期49卷 1299-1304页

作者： MENg Xiang-guo WANg Ji-Suo LIANg bao-long Department of Physics Liaocheng University Liaocheng 252059 China

In this paper, the two-mode excited squeezed vacuum state （TESVS） is studied by using the statistical method. By calculating the normalization of the TESVS, a new form of Jacobi polynomials and some new identities are obtained. The photon number distribution of the TESVS is given and it is a simple form of Jacobi polynomials. Using the entangled state representation of Wigner operator, the Wigner function of the TESVS is obtainded and the variations of the Wigner function with the parameters m, n, and r are discussed. Here from the phase space point of view the TESVS can be well interpreted and described.

关键词： two-mode excited squeezed vacuum state photon number distribution Wigner function entangled state representation

Husimi Functions of Excited Squeezed Vacuum States

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Communications in Theoretical Physics 2009年第9期52卷 487-492页

作者： MENg Xiang-guo WANg Ji-Suo LIANg bao-long Department of Physics Liaocheng University Liaocheng 252059 China

Based on the Husimi operator in pure state form introduced by Fan et al,which is a squeezed coherentstate projector,and the technique of integration within an ordered product (IWOP) of operators,as well as the entangledstate representations,we obtain the Husimi functions of the excited squeezed vacuum states (ESVS) and two marginaldistributions of the Husimi functions of the ESVS.

关键词： excited squeezed vacuum state IWOP technique entangled state representation Husimi operator Husimi function marginal distribution

A method for observing the three-dimensional morphologies of inclusions in steel

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International Journal of Minerals,Metallurgy and Materials 2012年第2期19卷 111-115页

作者： Yan-ping bao Min Wang wei Jiang State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China Journals Publishing Center University of Science and Technology Beijing Beijing 100083 China

A method for observing the three-dimensional morphologies of inclusions by deeply eroding a steel sample with a kind of organic solution composed of bromine water, acetone, and HCl （volume ratio, 45：45：10） was introduced. Four different kinds of inclusions in ultra low carbon steel were compared by metallographic observation and erosion observation. The results show that the three-dimensional morphologies of different kinds of inclusions could be observed clearly and simply after erosion. The method is useful for the observation and analysis of inclusions made by deep erosion. It also provides a new way to control and remove inclusions based on the true morphologies of inclusions.

关键词： inclusions morphology erosion ultra low carbon steel

Mechanical and electromagnetic wave absorption properties of Cf-Si3N4 ceramics with PyC/SiC interphases

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Journal of Materials Science & Technology 2019年第12期35卷 2809-2813页

作者： wei Zhou Lan long Yang Li College of Metallurgy and Materials Engineering Hunan University of TechnologyZhuzhou 412008China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Aiming to obtain microwave absorbing materials with excellent mechanical and microwave absorption properties, carbon fiber reinforced Si3N4 ceramics(Cf-Si3N4) with pyrolytic carbon(PyC)/SiC interphases were fabricated by gel casting. The influences of carbon fibers content on mechanical and microwave absorption properties of as-prepared Si3N4 based ceramics were investigated. Results show that chemical compatibility between carbon fibers and Si3N4 matrix in high temperature environment can be significantly improved after introduction of Py C/SiC interphases. As carbon fibers content increases from 0 to 4 wt%, flexural strength of Si3N4 based ceramics decreases slightly while fracture toughness obviously increases. Moreover, both the real and imaginary parts of complex permittivity increase with the rising of carbon fibers content within the frequency range of 8.2–12.4 gHz. Investigation of microwave absorption shows that the microwave attenuation ability of Cf-Si3N4 ceramics with Py C/SiC interphases is remarkably enhanced compared with pure Si3N4 ceramics. Effective absorption bandwidth(gHz and the minimum reflection less of-19.6 d B are obtained for Si3N4 ceramics with 4 wt%carbon fibers in 2.0 mm thickness. Cf-Si3N4 ceramics with Py C/SiC interphases are promising candidates for microwave absorbing materials with favorable mechanical property.

关键词： Silicon nitride Carbon fibers PyC/SiC interphases Mechanical properties Microwave absorption

Interface Instability of Diamond Crystals at High Temperature and High Pressure

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Chinese Physics Letters 2002年第3期19卷 419-421页

作者： Yin long-wei, Li Mu-Sen School of Materials Science and Engineering Shandong University and Ji'nan 250061 National Key Laboratory for Superhard Materials Jilin University Changchun 130012

Diamond growth instability at high temperature and high pressure (HPHT) has been elucidated by observing the cellular interface in diamond crystals. The HPHT diamond crystals grow layer by layer from solution of carbon in the molten catalyst. In the growth of any other crystals from solution, the growth interface is not stable and should be of the greatest significance to understand further the diamond growth mechanism. During the diamond growth, the carbon atoms are delivered to the growing diamond crystal by diffusion through a diamond crystal-solution boundary layer. In front of the boundary layer, there is a narrow constitutional supercooling zone related to the solubility difference between diamond and graphite in the molten catalyst. The diamond growth stability is broken, and the flat or planar growth interface transforms into a cellular interface due to the light supercooling. The phenomenon of solute trails in the diamonds was observed, the formation of solute trails was closely associated with the cellular interface

关键词： Diamonds

Characterization of growth Hillocks on the Surface of High-Pressure Synthetic Diamond

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Chinese Physics Letters 2002年第11期19卷 1707-1710页

作者： Yin long-wei, Li Mu-Sen College of Materials Science and Engineering Shandong University Ji'nan 250061 College of Mechanical Science and Engineering Shandong University Ji'nan 250061 National Key Laboratory for Superhard Materials Jilin University Changchun 130012

Diamond crystals, with dimensions of about 0.5-0.6 mm, were synthesized in the presence of Fe-Ni and Fe-Ni-Si catalyst solvents under high-pressure-high-temperature (HPHT) conditions. The as-known dendritic pattern was clearly seen on the (111) or (100) planes of diamond single crystals grown using Fe-Ni as a catalyst solvent. However, the conventional dendritic pattern was not observed in diamonds grown in the presence of Fe-Ni-Si alloy catalyst. Trigonal-type, pyramid-type, polygonal-type and rectangular-type growth hillocks were clearly observed on the (111) and (100) surfaces of diamonds grown from the Fe-Ni-Si-C system, and the density of the hillocks is very high at some positions. Clear successive growth layers can also be found on the (111) planes of the high-pressure diamond single crystals grown in the presence of Fe-Ni-Si alloy catalyst. The growth hillocks distributed on the (111) and (100) planes of the diamonds generally occur on or near growth steps, and some of the hillocks terminate at certain solid inclusions and voids. growth hillocks on the (111) and (100) surfaces directly indicate the spiral growth mechanism under HPHT. A possible formation process for growth hillocks is proposed.

关键词： Nickel alloys

InStereo2K: a large real dataset for stereo matching in indoor scenes

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Science China(Information Sciences) 2020年第11期63卷 136-146页

作者： wei bao wei WANg Yuhua XU Yulan gUO Siyu HONg Xiaohu ZHANg School of Electrical Engineering and Automation Hefei University of Technology School of Electronics and Communication Engineering Sun Yat-sen University College of Electronic Science and Technology National University of Defense Technology School of Aeronautics and Astronautics Sun Yat-sen University

Deep neural networks have shown great success in stereo matching in recent years. On the KITTI datasets, most top performing methods are based on neural networks. However, on the Middlebury datasets,these methods usually do not perform well. The KITTI datasets are collected in outdoor scenes while the Middlebury datasets are collected in indoor scenes. It is commonly believed that the community still lacks a large labelled dataset for stereo matching in indoor scenes. In this paper, we introduce a new stereo dataset called InS tereo2K. It contains 2050 pairs of stereo images with highly accurate groundtruth disparity maps, including 2000 pairs for training and 50 pairs for test. Experimental results show that our dataset can significantly improve the performance of several latest networks(including StereoNet and PSMNet) on the Middlebury 2014 dataset. The large scale, high accuracy and rich diversity of the proposed InS tereo2K dataset provide new opportunities to researchers in the area of stereo matching and beyond. It also takes end-to-end stereo matching methods a step towards practical applications.

关键词： stereo matching depth estimation convolutional neural network dataset