检索结果-南通市图书馆

Quantum computing for the Lipkin model with unitary coupled cluster and structure learning ansatz

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2022年第2期46卷 131-139页

作者：近岡旭梁豪兆 Department of Physics Graduate School of ScienceThe University of TokyoTokyo 113-0033Japan RIKEN Nishina Center Wako 351-0198Japan

We report a benchmark calculation for the Lipkin model in nuclear physics with a variational quantum eigensolver in quantum *** attention is paid to the unitary coupled cluster(UCC)ansatz and structure learning(SL)ansatz for the trial wave *** with both the UCC and SL ansatz can reproduce the ground-state energy well;however,it is found that the calculation with the SL ansatz performs better than thatwith the UCC ansatz,and the SL ansatz has even fewer quantum gates than the UCC ansatz.

关键词： Lipkin model quantum computing variational quantum eigensolver

Solving the Dirac Equation with Nonlocal Potential by Imaginary Time Step Method

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2009年第9期26卷 93-96页

作者：张颖梁豪兆孟杰 State Key Lab of Nuclear Physics and Technology School of Physics Peking University Beijing 100871 Institut de Physique Nucleaire IN2P3-CNRS and Universite Paris-Sud F-91406 Orsay Cedex France Department of Physics University of Stellenbosch Stellenbosch South Africa

The imaginary time step （ITS） method is applied to solve the Dirac equation with the nonlocal potential in coordinate space by the ITS evolution for the corresponding Schrfdinger-like equation for the upper component. It is demonstrated that the ITS evolution can be equivalently performed for the Schrodinger-like equation with or without localization. The latter algorithm is recommended in the application for the reason of simplicity and efficiency. The feasibility and reliability of this algorithm are also illustrated by taking the nucleus ^16O as an example, where the same results as the shooting method for the Dirae equation with localized effective potentials are obtained.

关键词： sea surface nonliear interaction numerical method

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

协变密度泛函理论中的张量力效应

原子核物理评论 2018年第4期35卷 390-400页

作者：梁豪兆申时行王之恒理化学研究所仁科加速器科学研究中心东京大学理学研究生院物理系北京大学物理学院北京100871 米兰大学物理系意大利米兰i20133 兰州大学核科学与技术学院兰州730000

张量力是核子-核子相互作用的重要成分,被认为是理解奇特原子核中壳结构演化规律的关键要素。然而,目前对于核介质中的张量力及其效应的定量认识,仍存在很多亟待解决的关键问题。着重梳理了在原子核密度泛函理论框架下,研究有效相互作... 详细信息

张量力是核子-核子相互作用的重要成分,被认为是理解奇特原子核中壳结构演化规律的关键要素。然而,目前对于核介质中的张量力及其效应的定量认识,仍存在很多亟待解决的关键问题。着重梳理了在原子核密度泛函理论框架下,研究有效相互作用中的张量力成分以及相应的张量力效应的相关工作,重点包括:基于相对论Hartree-Fock理论,以同位素链中的质子幻数壳演化为例,定量提取与分析其中的张量力效应;以及基于第一性原理的相对论Brueckner-Hartree-Fock理论,以中子滴单粒子能谱中的自旋-轨道劈裂演化为例,提出与张量力效应相关联的"准实验数据"。最后,展望原子核密度泛函理论今后可能的发展策略。

关键词：张量力效应壳结构演化自旋-轨道劈裂协变密度泛函理论相对论第一性原理计算

First attempt to overcome the disaster of Dirac sea in imaginary time step method

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2009年第S1期33卷 113-115页

作者：张颖梁豪兆孟杰 School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Institut de Physique Nucléaire IN2P3-CNRS and Université Paris-Sud F-91406 Orsay France Institute of Theoretical Physics Chinese Academy of Sciences Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Department of Physics University of Stellenbosch Stellenbosch South Africa

Efforts have been made to solve the Dirac equation with axially deformed scalar and vector WoodsSaxon potentials in the coordinate space with the imaginary time step method. The results of the singleparticle energies thus obtained are consistent with those calculated with the basis expansion method, which demonstrates the feasibility of the imaginary time step method for the relativistic static problems.

关键词： imaginary time step method Dirac equation Woods-Saxon potential axially deformed coordinate space

Perturbative pseudospin symmetry limit with linear spin-orbit potential

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2011年第9期35卷 825-828页

作者：李芳琼赵鹏巍梁豪兆 Guizhou University for Nationalities State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking University

The pseudospin symmetry （PSS） limits which conserve substantial spin-orbit splitting are investigated. It is found that while the strength of the spin-orbit potential as well as the spin-orbit splitting increase, the pseudospin doublets, e.g., 2p3/2 and lf5/2 states, are always degenerate. Furthermore, by examining the perturbation corrections to the single-particle energies, the perturbative nature of the proposed PSS limits is also discussed.

关键词： pseudospin symmetry spin-orbit splitting perturbation theory

在线全文

学校读者我要写书评

暂无评论

协变密度泛函框架下的原子核同位旋激发

协变密度泛函框架下的原子核同位旋激发

Relativistic Brueckner-Hartree-Fock Theory for Finite Nuclei

第十四届全国核物理大会暨第十届会员代表大会

作者：梁豪兆孟杰 Nguyen VanGiai 北京大学物理学院北京航空航天大学物理科学与核能工程学院 Institutde Physique Nucleaire and Universite Paris-SudOrsay 91406France

原子核同位旋激发是当前原子核物理、粒子物理和天体物理领域最重要的热点问题之一。本工作以相对论Hartree-Fock(RHF)理论为基础,建立了完全自洽的相对论无规位相近似(RPA),研究了原子核自旋-同位旋共振、原子核超允许衰变的同位旋修... 详细信息

原子核同位旋激发是当前原子核物理、粒子物理和天体物理领域最重要的热点问题之一。本工作以相对论Hartree-Fock(RHF)理论为基础,建立了完全自洽的相对论无规位相近似(RPA),研究了原子核自旋-同位旋共振、原子核超允许衰变的同位旋修正、以及

关键词：原子核同位旋激发协变密度泛函理论超允许衰变中微子-原子核反应截面

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Chinese Physics Letters 2016年第10期33卷 40-44页

作者：申时行胡金牛梁豪兆孟杰 Peter Ring 张双全 State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking University RIKEN Nishina Center Department of Physics Nankai University Department of Physics Graduate School of ScienceThe University of Tokyo School of Physics and Nuclear Energy Engineering Beihang University Department of Physics University of Stellenbosch Physik-Department der Technischen Universitt München

Starting with a bare nucleon-nucleon interaction, for the first time the full relativistic Brueckner Hartree-Fock equations are solved for finite nuclei in a Dirac-Woods-Saxon basis. No free parameters are introduced to calculate the ground-state properties of finite nuclei. The nucleus 160 is investigated as an example. The resulting groundstate properties, such as binding energy and charge radius, are considerably improved as compared with the non-relativistic Brueckner-Hartree-Fock results and much closer to the experimental data. This opens the door for ab initio covariant investigations of heavy nuclei.

关键词： in with for of Relativistic Brueckner-Hartree-Fock Theory for Finite Nuclei RHF been body is

Exploring effects of tensor force and its strength via neutron drops

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2021年第6期45卷 149-157页

作者：王之恒 Tomoya Naito 梁豪兆龙文辉 School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Department of Physics Graduate School of ScienceThe University of TokyoTokyo 113-0033Japan RIKEN Nishina Center Wako 351-0198Japan Joint Department for Nuclear Physics Lanzhou University and Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China

The tensor-force effects on the evolution of spin-orbit spittings in neutron drops are investigated within the framework of the relativistic Hartree-Fock *** a fair comparison on the pure mean-field level,the results of the relativistic Brueckner-Hartree-Fock calculation with the Bonn A interaction are adopted as *** a quantitative analysis,we certify that theπ-pscudovector(π-PV)coupling affects the evolutionary trend through the embedded tensor *** strength of the tensor force is explored by enlarging the strength fr of theπ-PV *** is found that weakening the density dependence of fn is slightly better than enlarging it with a *** thus provide a semiquantitative support for the renormalization persistency of the tensor force within the frame-work of density functional *** will serve as important guidance for further development of relativistic effective interactions with particular focus on the tensor force.

关键词： tensor force relativistic Hartree-Fock theory neutron drop tensor renormalization persistency

附加弯矩工况下管柱特殊螺纹接头密封性能仿真研究

在线全文

学校读者我要写书评

暂无评论

西安石油大学学报(自然科学版) 2024年

作者：梁豪樊恒任旭西安石油大学电子工程学院中海石油(中国)有限公司海南分公司

附加弯矩会对特殊扣管柱密封性能产生较大影响,为分析附加弯矩作用下特殊扣接头密封参数对接头的结构完整性和密封完整性的影响规律,依据实物测量和拉伸试验确定了管体几何尺寸、材料性能及螺纹几何尺寸及密封结构参数等,建立了特殊螺... 详细信息

附加弯矩会对特殊扣管柱密封性能产生较大影响,为分析附加弯矩作用下特殊扣接头密封参数对接头的结构完整性和密封完整性的影响规律,依据实物测量和拉伸试验确定了管体几何尺寸、材料性能及螺纹几何尺寸及密封结构参数等,建立了特殊螺纹接头的有限元模型。利用因素轮换法对不同影响因素进行了规律性分析。结果表明:附加弯矩的存在会影响接头密封面及台肩部位的密封性能;主密封过盈量控制在0.13 mm以内能有效控制特殊螺纹接头在装配过程中产生的塑性变形;密封面锥度范围控制在1:12～1:16之间能有效保证螺纹接头的完整性;密封面长度在3～7 mm范围内可保证特殊螺纹接头的良好工作状态;台肩角度为逆向角15°可提高接头的辅助密封效果,实现最佳的连接性能和可靠性。研究结论可为特殊螺纹结构的设计和性能优化提供参考。

关键词：特殊螺纹接头上扣扭矩因素轮换法有限元分析