Laser Control of Singlet-Pairing Process in an Ultracold Spinor Mixture

Abstract

In the mixture of ultracold spin-1 atoms of two different species A and B (e.g., 23 Na (A) and 87 Rb (B)), inter-species singlet-pairing process A+1 + B−1 A−1 + B+1 can be induced by the spindependent inter-atomic interaction, where subscript ±1 denotes the magnetic quantum number. Nevertheless, one cannot isolate this process from other spin-changing processes by tuning the bias real magnetic field. As a result, so far the singlet-pairing process have not been clearly observed in the experiments, and the measurement of the corresponding interaction strength becomes difficult.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 supperess 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 weakly singlet-pairing interaction strength and the entanglement generation of two different atoms.

Two-photon polarizability of Ba$^+$ ion: Control of spin-mixing process in an ultracold $^{137}$Ba$^+$--$^{87}$Rb mixture

“…Moreover, the two-photon process can induce coherent heteronuclear spin dynamics [26,61] and significantly influence the quantum phases of the binary-species spin-1 BEC [62][63][64]. Our model can be applied to other atomic mixture systems to generate entanglement between two different atoms [65,66] and control the singlet-pairing process [67]. The calculated two-photon dynamic polarizability and magic wavelengths in this work would be useful for quantum computing with 137 Ba + ion strings where the interrogating laser lights are state-dependent [68].…”