Gaussian time-dependent variational principle for the Bose-Hubbard model
文献类型：期刊论文
| 作者 | Guaita, Tommaso; Hack, Lucas; Shi, Tao3,4 ; Hubig, Claudius; Demler, Eugene2; Cirac, J. Ignacio
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| 刊名 | PHYSICAL REVIEW B
 |
| 出版日期 | 2019 |
| 卷号 | 100期号:9页码:94529 |
| 关键词 | VORTEX |
| ISSN号 | 2469-9950 |
| DOI | 10.1103/PhysRevB.100.094529 |
| 英文摘要 | We systematically extend Bogoliubov theory beyond the mean-field approximation of the Bose-Hubbard model in the superfluid phase. Our approach is based on the time-dependent variational principle applied to the family of all Gaussian states (i.e., Gaussian TDVP). First, we find the best ground-state approximation within our variational class using imaginary time evolution in 1D, 2D, and 3D. We benchmark our results by comparing to Bogoliubov theory and DMRG in 1D. Second, we compute the approximate one- and two-particle excitation spectrum as eigenvalues of the linearized projected equations of motion (linearized TDVP). We find the gapless Goldstone mode, a continuum of two-particle excitations and a doublon mode. We discuss the relation of the gap between Goldstone mode and two-particle continuum to the excitation energy of the Higgs mode. Third, we compute linear response functions for perturbations describing density variation and lattice modulation and discuss their relations to experiment. Our methods can be applied to any perturbations that are linear or quadratic in creation/annihilation operators. Finally, we provide a comprehensive overview how our results are related to well-known methods, such as traditional Bogoliubov theory and random phase approximation. |
| 学科主题 | Materials Science ; Physics |
| 语种 | 英语 |
| 源URL | [http://ir.itp.ac.cn/handle/311006/26988]  |
| 专题 | 理论物理研究所_理论物理所1978-2010年知识产出 |
| 作者单位 | 1.Harvard Univ, Lyman Lab, Dept Phys, 17 Oxford St, Cambridge, MA 02138 USA 2.Univ Chinese Acad Sci, CAS Ctr Excellence Topol Quantum Computat, Beijing 100049, Peoples R China 3.Chinese Acad Sci, Inst Theoret Phys, CAS Key Lab Theoret Phys, Beijing 100190, Peoples R China 4.Munich Ctr Quantum Sci & Technol, Schellingstr 4, D-80799 Munich, Germany 5.Max Planck Inst Quantum Opt, Hans Kopfennann Str 1, D-85748 Garching, Germany |
| 推荐引用方式 GB/T 7714 | Guaita, Tommaso,Hack, Lucas,Shi, Tao,et al. Gaussian time-dependent variational principle for the Bose-Hubbard model[J]. PHYSICAL REVIEW B,2019,100(9):94529. |
| APA | Guaita, Tommaso,Hack, Lucas,Shi, Tao,Hubig, Claudius,Demler, Eugene,&Cirac, J. Ignacio.(2019).Gaussian time-dependent variational principle for the Bose-Hubbard model.PHYSICAL REVIEW B,100(9),94529. |
| MLA | Guaita, Tommaso,et al."Gaussian time-dependent variational principle for the Bose-Hubbard model".PHYSICAL REVIEW B 100.9(2019):94529. |
入库方式： OAI收割
来源：理论物理研究所
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