Tunneling of two bosonic atoms from a one-dimensional anharmonic trap

Abstract

We investigate the quantum dynamics of two interacting bosonic atoms confined in a one-dimensional anharmonic trap. The tunneling rate, an experimentally measurable parameter of the system, was calculated as a function of the effective coupling interatomic constant $g$ from the ground (n=N=0) and first excited atomic states in the trap with respect to relative (n=2,N=0) and center-of-mass (n=0,N=2) atomic motion. This allows to investigate the initial population and pair correlation, as well as the effective coupling constant $g$, of the system by comparing the calculated tunneling rate with the experimental one. We have observed that the only possible tunneling scenario is a sequential particle tunneling in the cases we considered. We have also analyzed a rearrangement $(0,2)\rightleftarrows(2,0)$ of the spectrum in the limit $g\rightarrow \pm 0$ of noninteracting atoms.