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Operator-Algebraic Approach to the Yrast Spectrum of Weakly Interacting Trapped Bosons

Masahito Ueda·Tatsuya Nakajima
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Abstract

We present an operator-algebraic approach to deriving the low-lying quasi-degenerate spectrum of weakly interacting trapped N bosons with total angular momentum \hbar L for the case of small L/N, demonstrating that the lowest-lying excitation spectrum is given by 27 g n_3(n_3-1)/34, where g is the strength of the repulsive contact interaction and n_3 the number of excited octupole quanta. Our method provides constraints for these quasi-degenerate many-body states and gives higher excitation energies that depend linearly on N.

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Masahito Ueda, Tatsuya Nakajima. 2001-08-20. Operator-Algebraic Approach to the Yrast Spectrum of Weakly Interacting Trapped Bosons. https://doi.org/10.1103/physreva.64.063609

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