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arXiv · 0706.4077

Mapping the Evolution of Optically-Generated Rotational Wavepackets in a Room Temperature Ensemble of D$_2$

W. A. Bryan·E. M. L. English·J. McKenna·J. Wood·C. R. Calvert·R. Torres·I. C. E. Turcu·J. L. Collier·I. D. Williams·W. R. Newell
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Abstract

A coherent superposition of rotational states in D$_2$ has been excited by nonresonant ultrafast (12 femtosecond) intense (2 $\times$ 10$^{14}$ 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 D$_2$ wavepacket as a function of $θ$ and evolution time have been observed and modelled theoretically.

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W. A. Bryan, E. M. L. English, J. McKenna, J. Wood, C. R. Calvert, R. Torres, I. C. E. Turcu, J. L. Collier, I. D. Williams, W. R. Newell. 2007-06-27. Mapping the Evolution of Optically-Generated Rotational Wavepackets in a Room Temperature Ensemble of D$_2$. https://doi.org/10.1103/physreva.76.023414

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