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Physical Review A

Short-pulse photoassociation of K40 and Rb87 atoms in the vicinity of magnetically tuned Feshbach resonances

Xue‐Jin Hu, Jing-Lun Li, Ting Xie, Yong‐Chang Han, Shu‐Lin Cong

Published Sep 15, 2015• 8 citations
Publisher

Abstract

A Feshbach-optimized photoassociation for preparing ultracold $^{40}\mathrm{K}^{87}\mathrm{Rb}$ molecules with short pulses is investigated theoretically. The total probability density of the coupled hyperfine states is greatly enhanced at short interatomic separations in the vicinity of magnetically tuned Feshbach resonances. Due to the coupling of the free hyperfine state with different bound hyperfine states, the maximal probability density distributes at different interatomic regions and determines the choice of the intermediate state. By using the spin-orbit coupling of the excited states, the population is successfully transferred to the singlet ground state $X{\phantom{\rule{0.16em}{0ex}}}^{1}{\mathrm{\ensuremath{\Sigma}}}^{+}$ from the initial state mostly having triplet state character. By comparing the final population in the vicinity of Feshbach resonances at ${B}_{0}=546.80$ and 659.34 G, our results show that a Feshbach resonance corresponding to a more deeply bound vibrational level can enhance the photoassociation efficiency of ultracold atoms to some degree.

DOI
10.1103/physreva.92.032709

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