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arXiv · 0810.3207

Adaptive control of CO$_2$ bending vibration: deciphering field-system dynamics

G. -Y. Chen·Z. W. Wang·W. T. Hill III
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Abstract

We combined adaptive closed-loop optimization, phase-shaping with a restricted search space and imaging to control dynamics and decipher the optimal pulse. The approach was applied to controlling the amplitude of CO$_2$ bending vibration during strong-field Coulomb explosion. The search space was constrained by expressing the spectral phase as a Taylor series, which generated pulses with characteristics commensurate with the natural physical features of this problem. Optimal pulses were obtained that enhanced bending by up to 56% relative to what is observed with comparably intense, transform limited pulses. We show that (1) this judicious choice of a reduced parameter set made unwrapping the dynamics more transparent and (2) the enhancement is consistent with field-induced structural changes to a bent excited state of CO$_2^{2+}$, which theoretical simulations have identified as the state from which the explosion originates.

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G. -Y. Chen, Z. W. Wang, W. T. Hill III. 2008-10-17. Adaptive control of CO$_2$ bending vibration: deciphering field-system dynamics. https://doi.org/10.1103/physreva.79.011401

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