Coherence of Disordered Bosonic Gas with Two- and Three-Body Interactions

Redaouia Keltoum, Abdelâali Boudjemâa

Xin Zhang, Zi-Fa Yu, Ju-Kui Xue

We theoretically and numerically investigate the coherence of disordered bosonic gas with effective two- and three-body interactions within a two-site Bose–Hubbard model. By properly adjusting the two- and three-body interactions and the disorder, the coherence of the system exhibits new and interesting phenomena, including the resonance character of coherence against the disorder in the purely two- or three-body interactions system. More interestingly, the disorder and three-body interactions together can suppress the coherence of the purely three-body interactions system, which is different from the case in which the disorder and two-body interactions together can enhance the coherence in certain values of two-body interaction. Furthermore, when two- or three-body interactions are attractive or repulsive, the phase coherence exhibits completely different phenomena. In particular, if two- or three-body interactions are attractive, the coherence of the system can be significantly enhanced in certain regions. Correspondingly, the phase coherence of the system is strongly related to the effective interaction energy. The results provide a possible way for studying the coherence of bosonic gas with multi-atoms' interactions in the presence of the disorder.

Lennart Sobirey, Jonas Siegl, Niclas Luick +3 more

Dmitry S. Petrov

We propose a method of controlling two- and three-body interactions in an ultracold Bose gas in any dimension. The method requires us to have two coupled internal single-particle states split in energy such that the upper state is occupied virtually but amply during collisions. By varying system parameters, one can switch off the two-body interaction while maintaining a strong three-body one. The mechanism can be implemented for dipolar bosons in the bilayer configuration with tunneling or in an atomic system by using radio-frequency fields to couple two hyperfine states. One can then aim to observe a purely three-body interacting gas, dilute self-trapped droplets, the paired superfluid phase, Pfaffian state, and other exotic phenomena.

Arun K. Setty

Deke Li, Dun Zhao