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arXiv · 2407.05080

Observation of Space-Dependent Rotational Doppler Shifts with a Single Ion Probe

Nicolás Adrián Nuñez Barreto·Muriel Bonetto·Marcelo Alejandro Luda·Cecilia Cormick·Christian Tomás Schmiegelow
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Abstract

We present an experiment investigating the rotational Doppler effect using a single trapped ion excited by two copropagating vortex laser beams. The setup isolates the azimuthal gradients of the fields, eliminating longitudinal and curvature effects. We provide a detailed characterization of the phenomenon by deterministically positioning a single ion across the beams, achieving a signal which depends on the angular velocity of the ion and the difference of optical orbital angular momentum between the two beams. The interpretation of the measurements is supported by numerical simulations and by a simplified analytical model. Our results reveal key properties of the rotational Doppler effect, showing that it increases approaching the center of the beam and that it is independent of the waist of the beam. This offers insights into the feasibility of super-kicks or super-Doppler shifts for sensing and manipulating atomic motion transverse to the beams' propagation direction.

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Nicolás Adrián Nuñez Barreto, Muriel Bonetto, Marcelo Alejandro Luda, Cecilia Cormick, Christian Tomás Schmiegelow. 2024-07-06. Observation of Space-Dependent Rotational Doppler Shifts with a Single Ion Probe. https://arxiv.org/abs/2407.05080

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