  We have studied the formation of ultracold RbSr molecules with laser pulses.
After discussing the advantages of the Mott insulator phase for the control
with pulses, we present two classes of strategies. The first class involves two
electronic states. Two extensions of stimulated Raman adiabatic passage
(STIRAP) for multi-level transitions are used : alternating STIRAP (A-STIRAP)
and straddle STIRAP (S-STIRAP). Both transfer dynamics are modeled and
compared. The second class of strategies involves only the electronic ground
state and uses infrared (IR)/TeraHertz (THz) pulses. The chemical bond is first
created by the application of a THz chirped pulse or $\pi$-pulse. Subsequently,
the molecules are transferred to their ro-vibrational ground state using IR
pulses. For this last step, different optimized pulse sequences through optimal
control techniques, have been studied. The relative merits of these strategies
in terms of efficiency and robustness are discussed within the experimental
feasibility criteria of present laser technology.
