Composite-boson signature of atomic dimers in the interference pattern of colliding condensates

Shiue Yuan Shiau^1,2*, Aurelia Chenu³, Monique Combescot⁴

¹Physics Division, National Center for Theoretical Sciences, Hsinchu, Taiwan
²Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
³Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
⁴Institut des NanoSciences de Paris, Sorbonne Universite, Paris, France

* Presenter:Shiue Yuan Shiau, email:shiau.sean@gmail.com

We predict the existence of high frequency modes in the interference pattern of two colliding
condensates made of fermionic-atom dimers. These modes result from fermion exchanges between
condensates, and thus constitute a striking signature of the dimer composite nature. From the
2-composite-boson spatial correlation function, which we derive analytically, and the Shiva diagrams that
visualize many-body effects specific to composite bosons, we identify the physical origin of these
high frequency modes and determine the conditions to see them experimentally by using fermion
pairs trapped on optical lattice sites. The dimer granularity which appears in these modes comes
from Pauli blocking that prevents two dimers to be located at the same lattice site.

Keywords: Bose-Einstein condensate, Cold atom dimers, Interference, Composite bosons, Pauli exclusion principle