The stability condition and collective excitation of a trapped Bose-Einstein condensate with higher-order interactions

• Published in: Journal of physics. B, Atomic, molecular, and optical physics Vol. 46; no. 17; pp. 175301 - 1-9
• Main Authors: Qi, Wei, Liang, Zhaoxin, Zhang, Zhidong
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 14.09.2013; Institute of Physics
• Subjects: Bose-Einstein condensate; Bose-Einstein condensates; Classical and quantum physics: mechanics and fields; Collapse; collective excitations; Exact sciences and technology; Excitation; Matter waves; Physics; Scattering; Stability; Theoretical study; Mean field approximation; Two body system; Harmonic potential; Bose-Einstein condensation; Collective excitations
• ISSN: 0953-4075; 1361-6455
• DOI: 10.1088/0953-4075/46/17/175301

We take into account the higher-order corrections in two-body scattering interactions within a mean-field description, and investigate the stability conditions and collective excitations of a harmonically trapped Bose-Einstein condensate (BEC). Our results show that the presence of higher-order corrections causes drastic changes to the stability condition of a BEC. In particular, we predict that with the help of the higher-order interaction, a BEC can now collapse even for positive scattering lengths; whereas, a usually unstable BEC with a negative scattering length can be stabilized by positive higher-order effects. The low-lying collective excitations are significantly modified as well, compared to those without the higher-order corrections. The conditions for a possible experimental scenario are also proposed.