Laser control of the singlet-pairing process in an ultracold spinor mixture

In the mixture of ultracold spin-1 atoms of two different species A and B (e.g., Na-23 (A) and Rb-87 (B)), the interspecies singlet-pairing process A(+1) + B-1 reversible arrow A(-1) + B+1 can be induced by the spin-dependent interatomic interaction, where subscript +/- 1 denotes the magnetic quantum number. Nevertheless, one cannot isolate this process from other spin-changing processes, which are usually much stronger, by tuning the bias real magnetic field. As a result, it is difficult to clearly observe the singlet-pairing process and precisely measure the corresponding interaction strength. In this work we propose to control the singlet-pairing process via combining the real magnetic field and a laser-induced species-dependent synthetic magnetic field. With our approach one can significantly enhance this process and simultaneously suppress all other spin-changing processes. We illustrate our approach for both a confined two-atom system and a binary mixture of spinor Bose-Einstein condensates. Our control scheme is helpful for the precise measurement of the weak singlet-pairing interaction strength and the entanglement generation of two different atoms.

Automated summary

By combining a real magnetic field with a laser-induced species-dependent synthetic magnetic field, it is possible to control the interspecies singlet-pairing process in a mixture of ultracold spin-1 atoms, enhancing this process while suppressing other spin-changing processes. This approach is useful for precise measurement of weak singlet-pairing interaction strength and generation of entanglement between two different atoms.