Alkali-metal hydride molecules have large dipole moments in their ground electronic states. We explore the possibility of forming such molecules from a mixture of the ultracold atomic gases, employing a one-photon stimulated radiative association process. Using accurate molecular potential-energy curves and dipole moments, we have calculated the rate coefficients for populating each of the vibrational levels of the $X\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Sigma}^{+}$ states of LiH and NaH. We have found that significant molecule formation rates into the upper vibrational levels can be realized with laser intensities and atomic densities that are easily attainable experimentally. We examine the spontaneous emission cascade which takes place from these upper vibrational levels on a time scale of milliseconds, and calculate the resulting rotational populations in $v=0$ . We show that photon emission in the cascade process does not contribute to trap loss and that a large population of molecules in $v=0$ can be achieved.Alkali-metal hydride molecules have large dipole moments in their ground electronic states. We explore the possibility of forming such molecules from a mixture of the ultracold atomic gases, employing a one-photon stimulated radiative association process. Using accurate molecular potential-energy curves and dipole moments, we have calculated the rate coefficients for populating each of the vibrational levels of the $X\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Sigma}^{+}$ states of LiH and NaH. We have found that significant molecule formation rates into the upper vibrational levels can be realized with laser intensities and atomic densities that are easily attainable experimentally. We examine the spontaneous emission cascade which takes place from these upper vibrational levels on a time scale of milliseconds, and calculate the resulting rotational populations in $v=0$. We show that photon emission in the cascade process does not contribute to trap loss and that a large population of molecules in $v=0$ can be achieved.

Physical Review AApr 12, 200628 citations

Rovibrational Formation of Ultracold NaH Molecules Induced by an Ultrashort Laser Pulse

Qianzhen Su, Yu Jie, Niu Ying-Yu +1 more

The formation of the NaH molecule from unaligned ultracold atoms via photoassociation (PA) is theoretically investigated by numerically solving the time-dependent Schrödinger equation including the vibrational and rotational degrees of freedom. The PA processes via one- and two-photon excitations are described. The calculated results show that the associated molecule can be prepared to a desired rovibrational state of the ground electronic state for NaH. Compared with the one-photon association probability, the two-photon association probability is obviously enhanced.The formation of the NaH molecule from unaligned ultracold atoms via photoassociation (PA) is theoretically investigated by numerically solving the time-dependent Schrödinger equation including the vibrational and rotational degrees of freedom. The PA processes via one- and two-photon excitations are described. The calculated results show that the associated molecule can be prepared to a desired rovibrational state of the ground electronic state for NaH. Compared with the one-photon association probability, the two-photon association probability is obviously enhanced.

Chinese Physics LettersSep 1, 20105 citations

FORMING ULTRACOLD MOLECULES

Robin Côté

Dalgarno Celebratory SymposiumNov 1, 20090 citations

v=0

. We show that photon emission in the cascade process does not contribute to trap loss and that a large population of molecules in

v=0

can be achieved.