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arXiv · 1202.0559

Time-division multiplexing of the orbital angular momentum of light

Ebrahim Karimi·Lorenzo Marrucci·Corrado de Lisio·Enrico Santamato
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Abstract

We present an optical setup for generating a sequence of light pulses in which the orbital angular momentum (OAM) degree of freedom is correlated with the temporal one. The setup is based on a single $q$-plate within a ring optical resonator. By this approach, we demonstrate the generation of a train of pulses carrying increasing values of OAM, or, alternatively, of a controlled temporal sequence of pulses having prescribed OAM superposition states. Finally, we exhibit an "OAM-to-time conversion" apparatus dividing different input OAM states into different time-bins. The latter application provides a simple approach to digital spiral spectroscopy of pulsed light.

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Ebrahim Karimi, Lorenzo Marrucci, Corrado de Lisio, Enrico Santamato. 2012-02-02. Time-division multiplexing of the orbital angular momentum of light. https://doi.org/10.1364/ol.37.000127

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