S-wave and p-wave scattering in a cold gas of Na and Rb atoms

TL;DR

This paper computes low energy scattering parameters for Na-Rb atomic pairs using improved molecular potentials, analyzing s-wave and p-wave contributions, and identifying conditions for p-wave bound states and dominant scattering regimes.

Contribution

It introduces new scattering data for Na-Rb systems based on improved potentials and applies the variable phase method to analyze s-wave and p-wave scattering effects.

Findings

Identification of scattering lengths and volumes for Na-Rb isotopes.

Estimation of temperature thresholds for s-wave dominance.

Evidence for a near zero energy p-wave bound state.

Abstract

Using improved experimentally based $X{}^1\Sigma^+$ and $a{}^3\Sigma^+$ molecular potentials of NaRb, we apply the variable phase method to compute new data for low energy scattering of $^{23}$Na atoms by $^{85}$Rb atoms and $^{87}$Rb atoms. These are the scattering lengths and volumes, numbers of bound states and effective ranges, which we use to obtain the low energy spin-change cross section as functions of the system temperature and the isotope masses. From an analysis of the contributions of s-wave and p-wave scatterings to the elastic cross section we estimate temperatures below which only s-wave scattering is dominant. We compare our quantal results to data obtained from the semiclassical approximation. We supply evidence for the existence of a near zero energy p-wave bound state supported by the singlet molecular potential.