Mapping the Evolution of Optically-Generated Rotational Wavepackets in a Room Temperature Ensemble of D₂

الأصل · EN

A coherent superposition of rotational states in D₂ has been excited by nonresonant ultrafast (12 femtosecond) intense (2 × 10¹⁴ Wcm⁻²) 800 nm laser pulses leading to impulsive dynamic alignment. Field-free evolution of this rotational wavepacket has been mapped to high temporal resolution by a time-delayed pulse, initiating rapid double ionization, which is highly sensitive to the angle of orientation of the molecular axis with respect to the polarization direction, θ. The detailed fractional revivals of the neutral D₂ wavepacket as a function of θ and evolution time have been observed and modelled theoretically.