Influence of interactions beyond two-body interaction on the collapse of Bose–Einstein condensate in the attractive regime

Abstract

The Physics of Bose–Einstein Condensation drastically changes when the interaction is switched from repulsive to attractive, giving rise to new phenomena such as the condensate collapse or the so-called “Bosenova”. Numerous theoretical and experimental studies have investigated the collapse of BEC in the past, and an instability condition for BEC was proposed. However, there is a discrepancy between the theoretically predicted and experimentally obtained values of the instability parameter ( 𝑘 ). In this study, we numerically solve the Gross–Pitaevskii equation (GPE) and find a 𝑘 value that agrees better than the earlier theoretically predicted one. We incorporate higher-order interaction terms into the GPE and, by accounting for the experimentally observed 25%–40% particle loss on collapse, we find values of 𝑘 in the range of 0.332–0.415, which closely aligns with the experimentally obtained range. Hence, it is shown that the experimentally obtained range of values of 𝑘 is better described theoretically when the specific trap geometry, the observed particle loss, and higher-order interaction terms are considered.