Many-body excitation spectra of trapped bosons with general interaction by linear response

23rd International Laser Physics Workshop

Alon, Ofir E.^1

Department of Physics, University of Haifa at Oranim, Tivon

36006, Israel^1

关键词: Bogoliubov-de Gennes equations;    Bose-Einstein condensates;    Complex transformations;    Harmonic interactions;    Inter-particle interaction;    Linear-response theory;    Long range interactions;    Trapped interacting bosons;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/594/1/012039/pdf
DOI  :  10.1088/1742-6596/594/1/012039

来源: IOP

【 摘 要 】

The linear-response theory of the multiconfigurational time-dependent Hartree for bosons method (LR-MCTDHB) for computing many-body excitations of trapped Bose-Einstein condensates [Phys. Rev. A 88, 023606 (2013); J. Chem. Phys. 140, 034108 (2014)] is implemented, for the first time, for systems with general interparticle interaction. This allows us to investigate the many-body excitation spectrum of interacting bosons with, for instance, a long-range interaction. Illustrative numerical examples for repulsive and attractive bosons are provided. The LR-MCTDHB theory is capable of identifying all excitations, including the excitations which are not unraveled within Bogoliubov-de Gennes equations. The theory is herewith benchmarked against the exactly-solvable one-dimensional harmonic-interaction model. As a complementary result, using a complex transformation, we represent LR-MCTDHB in a compact block-diagonal form, opening up thereby an avenue for treating larger many-body systems. We expect the LR-MCTDHB theory and its implementation for general interparticle interaction to provide a proved probe into the many-body excitations involved in the out-ofequilibrium dynamics of trapped interacting bosons.