Open AccessStudy of Zero Temperature Ground State Properties of the Repulsive Bose-Einstein Condensate in an Anharmonic Trap
Author(s) -
Pankaj Kumar Debnath
Publication year - 2021
Publication title -
journal of scientific research
Language(s) - English
Resource type - Journals
eISSN - 2070-0245
pISSN - 2070-0237
DOI - 10.3329/jsr.v13i3.50811
Subject(s) - anharmonicity , bose–einstein condensate , ground state , physics , van der waals force , kinetic energy , potential energy , quartic function , harmonic , trapping , zero temperature , quantum mechanics , atomic physics , chemistry , molecule , mathematics , pure mathematics , ecology , biology
The zero-temperature ground state properties of experimental 87Rb condensate are studied in a harmonic plus quartic trap [ V(r) = ½mω2r2 + λr4 ]. The anharmonic parameter (λ) is slowly tuned from harmonic to anharmonic. For each choice of λ, the many-particle Schrödinger equation is solved using the potential harmonic expansion method and determines the lowest effective many-body potential. We utilize the correlated two-body basis function, which keeps all possible two-body correlations. The use of van der Waals interaction gives realistic pictures. We calculate kinetic energy, trapping potential energy, interaction energy, and total ground state energy of the condensate in this confining potential, modelled experimentally. The motivation of the present study is to investigate the crucial dependency of the properties of an interacting quantum many-body system on λ. The average size of the condensate has also been calculated to observe how the stability of repulsive condensate depends on anharmonicity. In particular, our calculation presents a clear physical picture of the repulsive condensate in an anharmonic trap.