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Quantum second-order optimization algorithm for general polynomials

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Science China(Physics,Mechanics & Astronomy) 2021年第10期64卷 54-63页

作者： Pan Gao Keren Li shijie wei Gui-Lu Long State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China Shenzhen JL Computational Science and Applied Research Institute Shenzhen 518109China Beijing Academy of Quantum Information Sciences Beijing 100193China Beijing National Research Center for Information Science and Technology and School of Information Tsinghua UniversityBeijing 100084China Frontier Science Center for Quantum Information Beijing 100084China

Quantum optimization algorithms can outperform their classical counterpart and are key in modern technology. The second-order optimization algorithm(the Newton algorithm) is a critical optimization method, speeding up the convergence by employing the second-order derivative of loss functions in addition to their first derivative. Here, we propose a new quantum second-order optimization algorithm for general polynomials with a computational complexity of O(poly(log d)). We use this algorithm to solve the nonlinear equation and learning parameter problems in factorization machines. Numerical simulations show that our new algorithm is faster than its classical counterpart and the first-order quantum gradient descent algorithm. While existing quantum Newton optimization algorithms apply only to homogeneous polynomials, our new algorithm can be used in the case of general polynomials, which are more widely present in real applications.

关键词： quantum computation quantum algorithm optimization

Reconstructing unknown quantum states using variational layerwise method

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Frontiers of physics 2022年第5期17卷 137-148页

作者： Junxiang Xiao Jingwei Wen shijie wei Guilu Long State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China Beijing Academy of Quantum Information Sciences Beijing 100193China Frontier Science Center for Quantum Information Beijing 100084China Beijing National Research Center for Information Science and Technology Beijing 100084China

In order to gain comprehensive knowledge of an arbitrary unknown quantum state,one feasible way is to reconstruct it,which can be realized by finding a series of quantum operations that can refactor the unitary evolution producing the unknown *** design an adaptive framework that can reconstruct unknown quantum states at high fidelities,which utilizes SWAP test,parameterized quantum circuits(PQCs)and layerwise learning *** conduct benchmarking on the framework using numerical simulations and reproduce states of up to six qubits at more than 96%overlaps with original states on average using PQCs trained by our framework,revealing its high applicability to quantum systems of different scales ***,we perform experiments on a five-qubit IBM Quantum hardware to reconstruct random unknown single qubit states,illustrating the practical performance of our *** a certain reconstructing fidelity,our method can effectively construct a PQC of suitable length,avoiding barren plateaus of shadow circuits and overuse of quantum resources by deep circuits,which is of much significance when the scale of the target state is large and there is no a priori information on *** advantage indicates that it can learn credible information of unknown states with limited quantum resources,giving a boost to quantum algorithms based on parameterized circuits on near-term quantum processors.

关键词： variational quantum algorithm layerwise learning quantum state reconstructing

Variational quantum attacks threaten advanced encryption standard based symmetric cryptography

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Science China(Information Sciences) 2022年第10期65卷 31-42页

作者： Zeguo WANG shijie wei Gui-Lu LONG Lajos HANZO State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua University Beijing Academy of Quantum Information Sciences Beijing National Research Center for Information Science and Technology School of Information Tsinghua University Frontier Science Center for Quantum Information Department of Electronics and Computer Science (ECS) University of Southampton

We propose a variational quantum attack algorithm(VQAA) for classical advanced encryption standard(AES)-like symmetric cryptography, as exemplified by the simplified-data encryption standard(S-DES). In the VQAA, the known ciphertext is encoded as the ground state of a Hamiltonian that is constructed through a regular graph, and the ground state can be found using a variational approach. We designed the ansatz and cost function for the S-DES’s variational quantum attack. It is surprising that sometimes the VQAA is even faster than Grover’s algorithm as demonstrated by our simulation results. The relationships of the entanglement entropy, concurrence, and the cost function are investigated, which indicate that entanglement plays a crucial role in the speedup.

关键词： S-DES VQA ansatz cost function optimization

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QCSH:A full quantum computer nuclear shell-model package

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Science China(Physics,Mechanics & Astronomy) 2023年第4期66卷 1-12页

作者： Peng Lv shijie wei Hao-Nan Xie Guilu Long Beijing Academy of Quantum Information Sciences Beijing 100193China State Key Laboratory of Low-Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China

The nuclear system is a promising area for demonstrating practical quantum advantage.A comprehensive computation of a nuclear system in a classical computer is beyond the capacity of current classical *** the rapid development of hardware,the prospect of using quantum computers in nuclear physics is close at *** this paper,we report a full quantum package,QCSH,for solving a nuclear shell model in a quantum *** uses the linear combination of the unitary formalism of quantum computing and performs all calculations in a quantum *** complexities of qubit resource and the number of basic gates of QCSH are both polynomials to the number of nucleons in *** example,QCSH is used to calculate the binding energies of 12 light nuclei(i.e.,^(2)H,^(3)H,^(3)He,^(4)He,^(6)Li,^(7)Li,^(12)C,^(14)N,^(16)O,^(17)O,^(23)Na,and^(40)Ca).Moreover,we experimentally demonstrate the calculation of deuteron binding energy using a superconducting quantum *** result indicates that QCSH can provide meaningful results already in near-term quantum devices.

关键词： quanutm simulation nuclear shell model linear combination of unitary operations quantum gradient descent

Preparation and pharmacokinetic study of fenofibrate cubic liquid crystalline

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Asian Journal of Pharmaceutical Sciences 2017年第6期12卷 580-585页

作者： shijie wei Jingbo Ren Ning Li Wuzhen Huo Chongkai Gao Guangdong Provincial Engineering Center of topical precise drug delivery system Guangdong Pharmaceutical UniversityGuangzhouGuangdongChina Department of Pharmaceutics School of PharmacyGuangdong Pharmaceutical UniversityGuangzhouGuangdongChina Research&Development Institute of Chinese Materia Medica Guangdong Pharmaceutical UniversityGuangzhouGuangdongChina

An LCC delivery system for Fenofibrate (Fen) was developed to improve its poorly oral bioavailability. Fen-LCC preparation methods were screened, and the prepared Fen-LCC was then characterized by a polarizing microscope and transmission electron microscopy (TEM).The spray drying technique was selected to dry and solidify particles into powder. The in vitro release of Fen-LCC was measured and in vivo pharmacokinetic experiments were carried out on rats after oral administration. Particles prepared through the high-temperature input method exhibited structural characteristics of LCC, and re-dissolved particles maintained the same features. The LCC delivery system can significantly improve in vitro release outcomes. After oral administration, AUCs of the suspension and LCC systems were measured at 131.6853 μg·h/ml and 1435.72893 μg·h/ml, respectively. The spray drying process presented here better maintains cubic structures, and the LCC system significantly improves bioavailability levels.

关键词： Lipid cubic liquid crystalline Fenofibrate Spray drying Bioavailability

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新三板促进企业融资和创投退出研究

中国科技论坛 2013年第5期 137-142页

作者：魏世杰中国科学技术发展战略研究院科技投资研究所北京100038

目前在国内各场外交易市场中,中关村新三板市场发展最长、制度最健全,几年来在为挂牌企业直接融资方面起到了非常重要的作用,也为创投退出提供了重要通道,为企业融资和创投退出提供了一个契合点。但作为建设全国性场外交易市场条件最成... 详细信息

目前在国内各场外交易市场中,中关村新三板市场发展最长、制度最健全,几年来在为挂牌企业直接融资方面起到了非常重要的作用,也为创投退出提供了重要通道,为企业融资和创投退出提供了一个契合点。但作为建设全国性场外交易市场条件最成熟的市场,新三板自身建设还存在一些亟待解决的问题,如挂牌企业区域限定过窄、普通自然人无法投资、交易制度落后等。因此,应加快推进新三板的建设和制度完善,进一步提高企业融资和创投退出效率。

关键词：场外交易市场创投直接融资退出

新时代我国引导社会资金投入科学研究的支持政策研究

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中国软科学 2021年第5期 59-69页

作者：薛薇魏世杰中国科学院科技战略咨询研究院北京100190 中国科学技术发展战略研究院北京100038

我国科学研究(基础研究与应用研究)必须走多元化投入之路,但是现有投入渠道狭窄、低效、不畅阻碍了私人部门的投入意愿,需要建立有效的政策激励制度。在借鉴美国科学研究多元化投入的政府措施基础上,提出进一步发挥政府对不同研究资源的... 详细信息

我国科学研究(基础研究与应用研究)必须走多元化投入之路,但是现有投入渠道狭窄、低效、不畅阻碍了私人部门的投入意愿,需要建立有效的政策激励制度。在借鉴美国科学研究多元化投入的政府措施基础上,提出进一步发挥政府对不同研究资源的"粘合剂"作用、建立全新的科技类非营利组织管理制度与支持政策以及制定支持社会资金投入科学研究的税收激励政策等政策措施。

关键词：基础研究应用研究科学捐赠非营利组织

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中国创新政策体系存在的问题和完善思路

中国科技论坛 2017年第2期 5-10页

作者：魏世杰中国科学技术发展战略研究院北京100038

近十年以来,中国创新政策体系已经基本形成,为创新发展营造了良好的环境,但是也存在各种问题阻碍了创新政策的发展,同时存在着创新政策盲点。为适应新形势的发展,创新政策体系还要在构建鼓励创新的社会环境、激发全社会创新活力等方面... 详细信息

近十年以来,中国创新政策体系已经基本形成,为创新发展营造了良好的环境,但是也存在各种问题阻碍了创新政策的发展,同时存在着创新政策盲点。为适应新形势的发展,创新政策体系还要在构建鼓励创新的社会环境、激发全社会创新活力等方面不断完善,实现建设国家创新体系的目标。

关键词：创新政策政策盲点创新主体国家创新体系

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我国股权激励税收政策的主要问题与政策建议

中国科技论坛 2013年第10期 30-35页

作者：薛薇魏世杰中国科学技术发展战略研究院北京100038

我国民营科技企业为吸引、培养和稳定高级管理或技术人才,一直在探索股权激励机制;高校和科研院所也一直探索技术入股后的股权分配。2009年开始,以中关村、东湖和张江国家自主创新示范区为代表的创新政策先行先试地区,积极开展科技型企... 详细信息

我国民营科技企业为吸引、培养和稳定高级管理或技术人才,一直在探索股权激励机制;高校和科研院所也一直探索技术入股后的股权分配。2009年开始,以中关村、东湖和张江国家自主创新示范区为代表的创新政策先行先试地区,积极开展科技型企业的股权激励试点工作,为有关政策的全国推广积累经验。但我国股权激励税收政策尚存在落实难、缺乏对长期股权持有和科技性中小企业的激励等问题,一定程度上阻碍了股权激励的发展和其在促进科技成果转化方面的积极作用。本文通过国际比较,深入分析了我国股权激励税收政策的主要问题,并提出政策建议。

关键词：股权激励科技企业个人所得税