Probing Photoinduced Two-Body Loss of Ultracold Nonreactive Bosonic Na23Rb87 and Na23K39 Molecules

Abstract

We probe photoinduced loss for chemically stable bosonic ${}^{23}\mathrm{Na}{}^{87}\mathrm{Rb}$ and ${}^{23}\mathrm{Na}{}^{39}\mathrm{K}$ molecules in chopped optical dipole traps, where the molecules spend a significant time in the dark. We expect the effective two-body decay to be significantly suppressed due to the small expected complex lifetimes of about 13 and $6\mu \mathrm{s}$ for ${}^{23}\mathrm{Na}{}^{87}\mathrm{Rb}$ and ${}^{23}\mathrm{Na}{}^{39}\mathrm{K}$, respectively. However, instead we do not observe any suppression of the two-body loss in parameter ranges where large loss suppressions are expected. We believe these unexpected results are most probably due to drastic underestimation of the complex lifetime by at least 1–2 orders of magnitude.