Cold atom–atom–ion three-body recombination of 4He–4He–X− (X = H or D)

Abstract

The atom–atom–ion three-body recombination (TBR) of mixed ⁴He and X⁻ (X = H or D) systems is investigated by solving the Schrödinger equation using the adiabatic hyperspherical representation method. It is shown that the dominant products after a TBR in the ultracold limit (E ≤ 0.1 mK × k_B) are different for the two systems. For the ⁴He⁴HeH⁻ system, the rate of TBR into the ⁴HeH⁻ ion is nearly two orders of magnitude larger than that of TBR into the neutral ⁴He₂ molecule. In contrast, the yield of ⁴He₂ is a little higher than that of ⁴HeD⁻ for the ⁴He⁴HeD⁻ system. Furthermore, since the adiabatic potentials become more attractive and the nonadiabatic couplings become much stronger by substituting D for H in the ⁴He⁴HeH⁻ system, the total TBR rate for the ⁴He⁴HeD⁻ system is nearly two orders of magnitude larger than that for the ⁴He⁴HeH⁻ system.