Universal three-body recombination via resonant d-wave interactions

For a system of three identical bosons interacting via short-range forces, when two of the atoms are about to form a two-body s-wave dimer, the Efimov effect takes place leading to the formation of an infinite number of three-body (Efimov) states. The lowest Efimov state crosses the three-body break-up threshold when the s-wave two-body scattering length is a≈-9.73r _vdW, r_vdW being the van der Waals length. This article focuses on a generalized version of this Efimov scenario, where two of the atoms are about to form a two-body d-wave dimer, resulting in strong d-wave interactions. In his paper, Bo Gao predicted that for broad resonances the d-wave dimer is always formed when a≈0.956r_vdW. Here we find that a single universal three-body state associated with the d-wave dimer is also formed near the three-body breakup threshold at a≈1.09r_vdW, or alternatively a₂=0.902r_vdW, where a₂ is the two-body d-wave scattering length. The signature of such a universal three-body state is signaled experimentally by an enhancement of the three-body recombination rate. The three-body effective potential curves that are crucial for understanding the recombination dynamics are also calculated and analyzed. An improved method to calculate the couplings, effective potential curves, and recombination rate coefficients is presented.