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

Numerical Solution of the Time Dependent 3D Schrödinger Equation Describing Tunneling of Atoms from Anharmonic Traps

“…We fix it by replacing the trap (6) with the "closed" sextic (i.e., the power series expansion of (6) up to x 6 j ) trapping potential [1,15] and calculating the eigenstates of the doubly excited relative and center-of-mass motion states of the stationary Schrödinger equation by using the numerical scheme from [12]. Figure 2 shows the fast convergence of the errors…”

“…The efficiency of our method is demonstrated in the solution of the topical problem of tunneling of cold atoms [1]. The atom-trap interaction is chosen of the standing-wave form:…”

“…For β = 0.427471, this models an actual atom-trap interaction [1,11,12] in modern experiments [13] on ultracold atoms (figure 1). The atom-atom interaction is taken of Gaussian form:…”

“…Pair correlation plays a major role in quantum tunneling and there are a only few works in the context of ultracold physics which accurately take into account the interatomic interaction [1][2][3][4][5][6][7]. In the present paper, we consider a tunneling of two interacting atoms from an anharmonic optical trap.…”

Tunneling of Two Interacting Fermions

“…In the context of ultracold physics, there are only a few works that completely take into account the pair correlation impact in the problem of a decay of a quantum system [1][2][3][4][5][6][7][8]. In this work we present an efficient method [1][2][3][4] which completely takes into account the interatomic interaction and also an external field.…”