Long-range states in excited ultracold 3He*-4He* dimers

TL;DR

This paper investigates long-range excited states of heteronuclear 3He*-4He* dimers using advanced calculations, revealing resonance groups and the influence of parity, but no bound states were found.

Contribution

It provides the first detailed multichannel analysis of these long-range states, highlighting the effects of Coriolis and non-adiabatic couplings on resonance structures.

Findings

Two groups of resonances predicted above the lowest energy

Resonances dissociate to different atomic excitations

No purely bound states were identified

Abstract

Long-range bound states of the excited heteronuclear 3He*--4He* system that dissociate to either 3He(1s2s 3S_1) + 4He(1s2p 3P_j) or 3He(1s2p 3P_j) + 4He(1s2s 3S_1), where j=0, 1, 2, are investigated using both single-channel and multichannel calculations in order to analyse the effects of Coriolis and non-adiabatic couplings. The multichannel calculations predict two groups of resonances above the lowest asymptotic energy. One of these groups dissociates to an atomic pair with the 2p excitation on the fermionic atom and the other dissociates to two asymptotes which correspond to the 2p excitation on either atom. Many of these resonances could be identified with levels in the single-channel calculation although the differences in energies were large. The total parity was found to have a significant influence on the ability to make these identifications. No purely bound states were found, although several resonances with line widths smaller than 1 MHz were obtained.