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arXiv · 1511.03165

Exact Diagonalization Study of Bose-Condensed Gas with Finite-Range Gaussian Interaction

Mohd. Imran·M. A. H. Ahsan
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Abstract

We investigate a system of $N$ spinless bosons confined in quasi-two-dimensional harmonic trap with repulsive two-body finite-range Gaussian interaction potential of large $s$-wave scattering length. Exact diagonalization of the Hamiltonian matrix is carried out to obtain the $N$-body ground state as well as low-lying excited states, using Davidson algorithm in beyond lowest-Landau-level approximation. We examine the finite-range effects of the interaction potential on the many-body ground state energy as also the degree of condensation of the Bose-condensed gas. The results obtained indicate that the finite-range Gaussian interaction potential enhances the degree of condensation compared to the zero-range interaction potential. We further analyze the effect of finite-range interaction potential on the breathing mode collective excitation. Our theoretical results may be relevant for experiments currently conducted on quasi-two-dimensional Bose gas with more realistic interaction potential.

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Mohd. Imran, M. A. H. Ahsan. 2015-11-10. Exact Diagonalization Study of Bose-Condensed Gas with Finite-Range Gaussian Interaction. https://doi.org/10.1166/asl.2015.6339

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