Cooling molecular vibrations with shaped laser pulses: Optimal control theory exploiting the timescale separation between coherent excitation and spontaneous emission

Understand

Laser cooling of molecules employing broadband optical pumping involves a timescale separation between laser excitation and spontaneous emission.

• Here, we optimize the optical pumping step using shaped laser pulses.
• We derive two optimization functionals to drive population into those excited state levels that have the largest spontaneous emission rates to the target state.
• We show that, when using optimal control, laser cooling of molecules works even if the Franck-Condon map governing the transitions is preferential to heating rather than cooling.