We perform a variational Monte Carlo study of the nematic state in iron-pnictide superconductors within a realistic five-orbital model. Our numerical results show that the nematic state, formed by introducing an aniso...We perform a variational Monte Carlo study of the nematic state in iron-pnictide superconductors within a realistic five-orbital model. Our numerical results show that the nematic state, formed by introducing an anisotropic hopping order into the projected wave function, is not stable unless the off-site Coulomb interaction V exceeds a critical value. This demonstrates that V plays a key role in forming the nematic state in iron-pnictide superconductors. In the nematic state,the orbital order and the anisotropic spin correlations are consistent with the experimental observations. We argue that the experimentally observed anisotropic magnetic couplings and structural transition are associated with the nematic state and can be understood in a unified framework.展开更多
The ground-state properties of a system with a small number of interacting bosons over a wide range of densities are investigated. The system is confined in a two-dimensional isotropic harmonic trap, where the interac...The ground-state properties of a system with a small number of interacting bosons over a wide range of densities are investigated. The system is confined in a two-dimensional isotropic harmonic trap, where the interaction between bosons is treated as a hard-core potential. By using variational Monte Carlo method, we diagonalize the one-body density matrix of the system to obtain the ground-state energy, condensate wavefunction and the condensate fraction. We find that in the dilute limit the depletion of central condensate in the 2D system is larger than in a 3D system for the same interaction strength; however as the density increases, the depletion at the centre of 2D trap will be equal to or even lower than that at the centre of 3D trap, which is in agreement with the anticipated in Thomas-Fermi approximation. In addition, in the 2D system the total condensate depletion is still larger than in a 3D system for the same scattering length.展开更多
Solving the ground state of quantum many-body systems remains a fundamental challenge in physics and chemistry.Recent advancements in quantum hardware have opened new avenues for addressing this challenge.Inspired by ...Solving the ground state of quantum many-body systems remains a fundamental challenge in physics and chemistry.Recent advancements in quantum hardware have opened new avenues for addressing this challenge.Inspired by the quantum-enhanced Markov chain Monte Carlo(QeMCMC)algorithm,which was originally designed for sampling the Boltzmann distribution of classical spin models using quantum computers,we introduce a quantum-assisted variational Monte Carlo(QA-VMC)algorithm for solving the ground state of quantum many-body systems by adapting QeMCMC to sample the distribution of a(neural-network)wave function in VMC.The central question is whether such a quantum-assisted proposal can potentially offer a computational advantage over classical methods.Through numerical investigations for the Fermi−Hubbard model and molecular systems,we demonstrate that the quantum-assisted proposal exhibits larger absolute spectral gaps and reduced autocorrelation times compared to conventional classical proposals,leading to more efficient sampling and faster convergence to the ground state in VMC as well as a more accurate and precise estimation of physical observables.This advantage is especially pronounced for specific parameter ranges,where the ground-state configurations are more concentrated in some configurations separated by large Hamming distances.Our results underscore the potential of quantum-assisted algorithms to enhance classical variational methods for solving the ground state of quantum many-body systems.展开更多
We investigate the origin of the 1/3 magnetization plateau in the S=1/2 kagome antiferromagnetic Heisenberg model using the variational Monte Carlo and exact diagonalization methods,to account for the recent experimen...We investigate the origin of the 1/3 magnetization plateau in the S=1/2 kagome antiferromagnetic Heisenberg model using the variational Monte Carlo and exact diagonalization methods,to account for the recent experimental observations in YCu_(3)(OH)_(6+x)Br_(3-x)and YCu_(3)(OD)_(6+x)Br_(3-x).We identify three degenerate valencebond-solid(VBS)states forming a√3×√3 unit cell.These states exhibit David-star patterns in the spin moment distribution with only two fractional values-1/3 and 2/3,and are related through translational transformations.While the spin correlations in these VBS states are found to be short-range,resembling a quantum spin liquid,we show that they have a vanishing topological entanglement entropy and thus are topologically trivial many-body states.Our theoretical results provide strong evidence that the 1/3 magnetization plateau observed in recent experiments arises from these√3×√3 VBS states with fractional spin moments.展开更多
In <span style="font-family:;" "="">the <span style="font-family:;" "="">framework of the variational Monte Carlo method, the ground states of the lithium ...In <span style="font-family:;" "="">the <span style="font-family:;" "="">framework of the variational Monte Carlo method, the ground states of the lithium atom and l<span style="font-family:;" "="">ithium like ions up to Z = 10 in an external strong magnetic field are evaluated. Furthermore, the two low-lying excited states <img src="Edit_d92f9e9d-e574-4fa3-91fb-a153db020509.png" alt="" /><span style="font-family:;" "="">, <span style="font-size:10.0pt;font-family:;" "=""><span style="font-size:10.0pt;font-family:;" "=""><span style="font-size:10.0pt;font-family:;" "=""><span style="font-size:10.0pt;font-family:;" "=""><span style="font-size:10.0pt;font-family:;" "=""><img src="data:image/png;base64,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" alt="" /> <img src="Edit_5bf0039b-89f7-4346-a3cb-178f5df359cf.png" width="0" height="0" alt="" /><img src="data:image/png;base64,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" alt="" /><img src="Edit_41f9b122-3fdc-4f01-9470-542944413516.png" alt="" /><span style="font-family:;" "="">and <img src="data:image/png;base64,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" alt="" /><span style="font-family:;" "=""> <img src="Edit_79f5e8c8-0b24-4dfd-8b9e-080183cc967f.png" alt="" />of the lithium atom in strong magnetic field are also investigated<span style="font-family:;" "="">. <span style="font-family:;" "="">Simple trial wave functions for lithium are used.展开更多
In Bayesian multi-target fltering,knowledge of measurement noise variance is very important.Signifcant mismatches in noise parameters will result in biased estimates.In this paper,a new particle flter for a probabilit...In Bayesian multi-target fltering,knowledge of measurement noise variance is very important.Signifcant mismatches in noise parameters will result in biased estimates.In this paper,a new particle flter for a probability hypothesis density（PHD）flter handling unknown measurement noise variances is proposed.The approach is based on marginalizing the unknown parameters out of the posterior distribution by using variational Bayesian（VB）methods.Moreover,the sequential Monte Carlo method is used to approximate the posterior intensity considering non-linear and non-Gaussian conditions.Unlike other particle flters for this challenging class of PHD flters,the proposed method can adaptively learn the unknown and time-varying noise variances while fltering.Simulation results show that the proposed method improves estimation accuracy in terms of both the number of targets and their states.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11274310,11474287,11174072,and 91221103)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20104208110001)
文摘We perform a variational Monte Carlo study of the nematic state in iron-pnictide superconductors within a realistic five-orbital model. Our numerical results show that the nematic state, formed by introducing an anisotropic hopping order into the projected wave function, is not stable unless the off-site Coulomb interaction V exceeds a critical value. This demonstrates that V plays a key role in forming the nematic state in iron-pnictide superconductors. In the nematic state,the orbital order and the anisotropic spin correlations are consistent with the experimental observations. We argue that the experimentally observed anisotropic magnetic couplings and structural transition are associated with the nematic state and can be understood in a unified framework.
文摘The ground-state properties of a system with a small number of interacting bosons over a wide range of densities are investigated. The system is confined in a two-dimensional isotropic harmonic trap, where the interaction between bosons is treated as a hard-core potential. By using variational Monte Carlo method, we diagonalize the one-body density matrix of the system to obtain the ground-state energy, condensate wavefunction and the condensate fraction. We find that in the dilute limit the depletion of central condensate in the 2D system is larger than in a 3D system for the same interaction strength; however as the density increases, the depletion at the centre of 2D trap will be equal to or even lower than that at the centre of 3D trap, which is in agreement with the anticipated in Thomas-Fermi approximation. In addition, in the 2D system the total condensate depletion is still larger than in a 3D system for the same scattering length.
基金supported by the Innovation Program for Quantum Science and Technology(Grant No.2023ZD0300200)the Fundamental Research Funds for the Central Universities.
文摘Solving the ground state of quantum many-body systems remains a fundamental challenge in physics and chemistry.Recent advancements in quantum hardware have opened new avenues for addressing this challenge.Inspired by the quantum-enhanced Markov chain Monte Carlo(QeMCMC)algorithm,which was originally designed for sampling the Boltzmann distribution of classical spin models using quantum computers,we introduce a quantum-assisted variational Monte Carlo(QA-VMC)algorithm for solving the ground state of quantum many-body systems by adapting QeMCMC to sample the distribution of a(neural-network)wave function in VMC.The central question is whether such a quantum-assisted proposal can potentially offer a computational advantage over classical methods.Through numerical investigations for the Fermi−Hubbard model and molecular systems,we demonstrate that the quantum-assisted proposal exhibits larger absolute spectral gaps and reduced autocorrelation times compared to conventional classical proposals,leading to more efficient sampling and faster convergence to the ground state in VMC as well as a more accurate and precise estimation of physical observables.This advantage is especially pronounced for specific parameter ranges,where the ground-state configurations are more concentrated in some configurations separated by large Hamming distances.Our results underscore the potential of quantum-assisted algorithms to enhance classical variational methods for solving the ground state of quantum many-body systems.
基金supported by the National Key Projects for Research and Development of China(Grant Nos.2021YFA1400400 and 2024YFA1408104)the National Natural Science Foundation of China(Grant Nos.12434005,12374137,and 92165205).
文摘We investigate the origin of the 1/3 magnetization plateau in the S=1/2 kagome antiferromagnetic Heisenberg model using the variational Monte Carlo and exact diagonalization methods,to account for the recent experimental observations in YCu_(3)(OH)_(6+x)Br_(3-x)and YCu_(3)(OD)_(6+x)Br_(3-x).We identify three degenerate valencebond-solid(VBS)states forming a√3×√3 unit cell.These states exhibit David-star patterns in the spin moment distribution with only two fractional values-1/3 and 2/3,and are related through translational transformations.While the spin correlations in these VBS states are found to be short-range,resembling a quantum spin liquid,we show that they have a vanishing topological entanglement entropy and thus are topologically trivial many-body states.Our theoretical results provide strong evidence that the 1/3 magnetization plateau observed in recent experiments arises from these√3×√3 VBS states with fractional spin moments.
文摘In <span style="font-family:;" "="">the <span style="font-family:;" "="">framework of the variational Monte Carlo method, the ground states of the lithium atom and l<span style="font-family:;" "="">ithium like ions up to Z = 10 in an external strong magnetic field are evaluated. Furthermore, the two low-lying excited states <img src="Edit_d92f9e9d-e574-4fa3-91fb-a153db020509.png" alt="" /><span style="font-family:;" "="">, <span style="font-size:10.0pt;font-family:;" "=""><span style="font-size:10.0pt;font-family:;" "=""><span style="font-size:10.0pt;font-family:;" "=""><span style="font-size:10.0pt;font-family:;" "=""><span style="font-size:10.0pt;font-family:;" "=""><img src="data:image/png;base64,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" alt="" /> <img src="Edit_5bf0039b-89f7-4346-a3cb-178f5df359cf.png" width="0" height="0" alt="" /><img src="data:image/png;base64,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" alt="" /><img src="Edit_41f9b122-3fdc-4f01-9470-542944413516.png" alt="" /><span style="font-family:;" "="">and <img src="data:image/png;base64,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" alt="" /><span style="font-family:;" "=""> <img src="Edit_79f5e8c8-0b24-4dfd-8b9e-080183cc967f.png" alt="" />of the lithium atom in strong magnetic field are also investigated<span style="font-family:;" "="">. <span style="font-family:;" "="">Simple trial wave functions for lithium are used.
基金supported by National High-tech Research and Development Program of China (No.2011AA7014061)
文摘In Bayesian multi-target fltering,knowledge of measurement noise variance is very important.Signifcant mismatches in noise parameters will result in biased estimates.In this paper,a new particle flter for a probability hypothesis density（PHD）flter handling unknown measurement noise variances is proposed.The approach is based on marginalizing the unknown parameters out of the posterior distribution by using variational Bayesian（VB）methods.Moreover,the sequential Monte Carlo method is used to approximate the posterior intensity considering non-linear and non-Gaussian conditions.Unlike other particle flters for this challenging class of PHD flters,the proposed method can adaptively learn the unknown and time-varying noise variances while fltering.Simulation results show that the proposed method improves estimation accuracy in terms of both the number of targets and their states.
