arXiv:2006.03484 · Physical Chemistry Chemical Physics

Nondestructive dispersive imaging of rotationally excited ultracold molecules

Qingze Guan, Michael Highman, Η. Meier, Garrett R. Williams, V. W. Scarola, Brian DeMarco, Svetlana Kotochigova, Bryce Gadway

Published Jan 1, 2020• 8 citations

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Abstract

A barrier to realizing the potential of molecules for quantum information science applications is a lack of high-fidelity, single-molecule imaging techniques. Here, we present and theoretically analyze a general scheme for dispersive imaging of electronic ground-state molecules. Our technique relies on the intrinsic anisotropy of excited molecular rotational states to generate optical birefringence, which can be detected through polarization rotation of an off-resonant probe laser beam. Using 23Na87Rb and 87Rb133Cs as examples, we construct a formalism for choosing the molecular state to be imaged and the excited electronic states involved in off-resonant coupling. Our proposal establishes the relevant parameters for achieving degree-level polarization rotations for bulk molecular gases, thus enabling high-fidelity nondestructive imaging. We additionally outline requirements for the high-fidelity imaging of individually trapped molecules.

DOI: 10.1039/d0cp03419c

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