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Updated: Nov 11, 2025

Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Observation of the rotational Doppler shift with spatially incoherent light
Abstract:
The rotational Doppler shift (RDS) is typically measured by illuminating a rotating target with a laser prepared in a simple, known orbital angular momentum (OAM) superposition. We establish theoretically and experimentally that detecting the rotational Doppler shift does not require the incident light to have a well-defined OAM spectrum but instead requires well-defined correlations within the OAM spectrum. We demonstrate measurement of the rotational Doppler shift using spatially incoherent light.
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