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Updated: Jun 14, 2026
10:52
Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Radiative force from optical cycling on a diatomic molecule
E S Shuman1, J F Barry, D R Glenn
1Department of Physics, Yale University, P.O. Box 208120, New Haven, Connecticut 06520, USA.
Physical Review Letters
|April 7, 2010
Summary
We developed optical cycling for strontium monofluoride (SrF) molecules using a specific electronic transition. This method enables over 100,000 photon scatters, paving the way for direct laser cooling of SrF.
Area of Science:
- Atomic, Molecular, and Optical Physics
- Quantum Chemistry
- Laser Spectroscopy
Background:
- Optical cycling is crucial for laser cooling of atoms and molecules.
- Polar molecules like strontium monofluoride (SrF) present unique challenges for optical cycling due to their complex energy level structures.
Purpose of the Study:
- To demonstrate a practical optical cycling scheme for the strontium monofluoride (SrF) molecule.
- To enable efficient photon scattering for potential laser cooling applications.
Main Methods:
- Utilizing the X2Sigma+ --> A2Pi(1/2) electronic transition in SrF.
- Leveraging highly diagonal Franck-Condon factors to minimize vibrational branching.
- Implementing a quasicycling N = 1 --> N' = 0 transition with magnetic field remixing to suppress rotational branching.
Main Results:
- Observed cycling fluorescence in an SrF molecular beam.
- Demonstrated deflection of the SrF molecular beam via radiative force, confirming successful optical cycling.
- Achieved suppression of both vibrational and rotational branching.
Conclusions:
- The developed scheme effectively enables optical cycling in SrF.
- The method shows potential for over 10^5 photon scatters, a key requirement for direct laser cooling.
- Further improvements could lead to the realization of direct laser cooling for SrF.
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