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arXiv · 1105.2413

Stark-selected beam of ground-state OCS molecules characterized by revivals of impulsive alignment

Jens H. Nielsen·Paw Simesen·Christer Z. Bisgaard·Henrik Stapelfeldt·Frank Filsinger·Bretislav Friedrich·Gerard Meijer·Jochen Küpper
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Abstract

We make use of an inhomogeneous electrostatic dipole field to impart a quantum-state-dependent deflection to a pulsed beam of OCS molecules, and show that those molecules residing in the absolute ground state, $X ^1\Sigma^+$, $\ket{00^00}$, J=0, can be separated out by selecting the most deflected part of the molecular beam. Past the deflector, we irradiate the molecular beam by a linearly polarized pulsed nonresonant laser beam that impulsively aligns the OCS molecules. Their alignment, monitored via velocity-map imaging, is measured as a function of time, and the time dependence of the alignment is used to determine the quantum state composition of the beam. We find significant enhancements of the alignment (\costhetasqtd $= 0.84$) and of state purity ($> 92$%) for a state-selected, deflected beam compared with an undeflected beam.

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Jens H. Nielsen, Paw Simesen, Christer Z. Bisgaard, Henrik Stapelfeldt, Frank Filsinger, Bretislav Friedrich, Gerard Meijer, Jochen Küpper. 2011-05-12. Stark-selected beam of ground-state OCS molecules characterized by revivals of impulsive alignment. https://doi.org/10.1039/c1cp21143a

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