The single reference second order Brillouin-Wigner perturbation theory recently developed, which eliminates its size-extensivity error, has been generalized to state-specific, multi-reference （SS-MR）, BWPT2 providin...The single reference second order Brillouin-Wigner perturbation theory recently developed, which eliminates its size-extensivity error, has been generalized to state-specific, multi-reference （SS-MR）, BWPT2 providing a size-extensive correction to the electron correlation problem for systems that demand the use of a multi-reference function. Illustrative numerical tests of the size-extensivity corrections are made for widely used molecules in their ground states, which are pronounced multi-reference characteristics. We have implemented two-reference and three-reference cases for CH2, BH and bond breaking process in the ground states of HF molecules. The results are compared with the rigorously size-extensive methods such as the M^ller-Plesset perturbation theory, i.e., MP2, full configuration interaction （Full-CI） and allied methods using the same basis sets.展开更多
The topological magnon insulator on a honeycomb lattice with Dzyaloshinskii–Moriya interaction(DMI) is studied under the application of a circularly polarized light.At the high-frequency regime, the effective tight-b...The topological magnon insulator on a honeycomb lattice with Dzyaloshinskii–Moriya interaction(DMI) is studied under the application of a circularly polarized light.At the high-frequency regime, the effective tight-binding model is obtained based on Brillouin–Wigner theory.Then, we study the corresponding Berry curvature and Chern number.In the Dirac model, the interplay between a light-induced handedness-dependent effective DMI and intrinsic DMI is discussed.展开更多
We introduce a decimation scheme of constructing renormalized Hamiltonian flows,which is useful in the study of properties of energy eigenfunctions,such as localization,as well as in approximate calculation of eigenen...We introduce a decimation scheme of constructing renormalized Hamiltonian flows,which is useful in the study of properties of energy eigenfunctions,such as localization,as well as in approximate calculation of eigenenergies.The method is based on a generalized Brillouin-Wigner perturbation theory.Each flow is specific for a given energy and,at each step of the flow,a finite subspace of the Hilbert space is decimated in order to obtain a renormalized Hamiltonian for the next step.Eigenenergies of the original Hamiltonian appear as unstable fixed points of renormalized flows.Numerical illustration of the method is given in the Wigner-band random-matrix model.展开更多
基金Supported by the Scientific and Technological Research Council of Turkey(TUBITAK)under Grant No 2219-1/2013
文摘The single reference second order Brillouin-Wigner perturbation theory recently developed, which eliminates its size-extensivity error, has been generalized to state-specific, multi-reference （SS-MR）, BWPT2 providing a size-extensive correction to the electron correlation problem for systems that demand the use of a multi-reference function. Illustrative numerical tests of the size-extensivity corrections are made for widely used molecules in their ground states, which are pronounced multi-reference characteristics. We have implemented two-reference and three-reference cases for CH2, BH and bond breaking process in the ground states of HF molecules. The results are compared with the rigorously size-extensive methods such as the M^ller-Plesset perturbation theory, i.e., MP2, full configuration interaction （Full-CI） and allied methods using the same basis sets.
基金Project supported by the National Natural Science Foundation of China(Grant No.61604106)Shandong Provincial Natural Science Foundation,China(Grant No.ZR2014FL025)
文摘The topological magnon insulator on a honeycomb lattice with Dzyaloshinskii–Moriya interaction(DMI) is studied under the application of a circularly polarized light.At the high-frequency regime, the effective tight-binding model is obtained based on Brillouin–Wigner theory.Then, we study the corresponding Berry curvature and Chern number.In the Dirac model, the interplay between a light-induced handedness-dependent effective DMI and intrinsic DMI is discussed.
基金Supported by the National Natural Science Foundation of China under Grant Nos.11275179,11535011,and 11775210
文摘We introduce a decimation scheme of constructing renormalized Hamiltonian flows,which is useful in the study of properties of energy eigenfunctions,such as localization,as well as in approximate calculation of eigenenergies.The method is based on a generalized Brillouin-Wigner perturbation theory.Each flow is specific for a given energy and,at each step of the flow,a finite subspace of the Hilbert space is decimated in order to obtain a renormalized Hamiltonian for the next step.Eigenenergies of the original Hamiltonian appear as unstable fixed points of renormalized flows.Numerical illustration of the method is given in the Wigner-band random-matrix model.
