Emission in CS2 vapor stimulated by a counterintuitive sequence of pulses

Measurement of the stimulated emission from a cell containing CS2 molecules irradiated by two laser pulses is discussed. Both an approximate adiabatic solution and an exact numerical solution have been used to explain the results. It has been proved that, to obtain maximal signal, the pulses must come to the cell in a counterintuitive order, that is, the stimulating pulse arrives prior to the pump pulse. The connection with the phenomenon of efficient population transfer has been pointed out.