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arXiv · 1201.6063

Spin-to-Orbital Angular Momentum Conversion and Spin-Polarization Filtering in Electron Beams

Ebrahim Karimi·Lorenzo Marrucci·Vincenzo Grillo·Enrico Santamato
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Abstract

We propose the design of a space-variant Wien filter for electron beams that induces a spin half-turn and converts the corresponding spin angular momentum variation into orbital angular momentum of the beam itself by exploiting a geometrical phase arising in the spin manipulation. When applied to a spatially coherent input spin-polarized electron beam, such a device can generate an electron vortex beam, carrying orbital angular momentum. When applied to an unpolarized input beam, the proposed device, in combination with a suitable diffraction element, can act as a very effective spin-polarization filter. The same approach can also be applied to neutron or atom beams.

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Ebrahim Karimi, Lorenzo Marrucci, Vincenzo Grillo, Enrico Santamato. 2012-01-29. Spin-to-Orbital Angular Momentum Conversion and Spin-Polarization Filtering in Electron Beams. https://doi.org/10.1103/physrevlett.108.044801

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