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arXiv · 1407.7678

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

Ofir E. Alon
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Abstract

The linear-response theory of the multiconfigurational time-dependent Hartree for bosons method for computing many-body excitations of trapped Bose-Einstein condensates [Phys. Rev. A {\bf 88}, 023606 (2013)] is implemented for systems with general interparticle interaction. Illustrative numerical examples for repulsive and attractive bosons are provided. The many-body linear-response theory identifies the excitations 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, we represent the theory in a compact block-diagonal form, opening up thereby an avenue for treating larger systems.

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Ofir E. Alon. 2014-07-29. Many-body excitation spectra of trapped bosons with general interaction by linear response. https://doi.org/10.1088/1742-6596/594/1/012039

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