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arXiv · 0910.4354

Rotational excitations in two-color photoassociation

Jisha Hazra·Bimalendu Deb
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Abstract

We show that it is possible to excite higher rotational states J > 2 in ultracold photoassociation by two laser fields. Usually higher J states are suppressed in photoassociation at ultracold temperatures in the regime of Wigner threshold laws. We propose a scheme in which one strong laser field drives photoassociation transition close to either J = 1 or J = 2 rotational state of a particular vibrational level of an electronically excited molecule. The other laser field is tuned near photoassociation resonance with J > 2 rotational levels of the same vibrational state. The strong laser field induces a strong continnum-bound dipole coupling. The resulting dipole force between two colliding atoms modifies the continnum states forming continnum-bound dressed states with a significant component of higher partial waves in the continnum configuration. When the second laser is scanned near the resonance of the higher J states, these states become populated due to photoassociative transitions from the modified continnum.

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Jisha Hazra, Bimalendu Deb. 2009-10-22. Rotational excitations in two-color photoassociation. https://doi.org/10.1103/physreva.81.022711

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