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arXiv · 1210.1772

The photonic wheel: demonstration of a state of light with purely transverse angular momentum

Peter Banzer·Martin Neugebauer·Andrea Aiello·Christoph Marquardt·Norbert Lindlein·Thomas Bauer·Gerd Leuchs
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Abstract

The concept of angular momentum is ubiquitous to many areas of physics. In classical mechanics, a system may possess an angular momentum which can be either transverse (e.g., in a spinning wheel) or longitudinal (e.g., for a fluidic vortex) to the direction of motion. Photons, however, are well-known to exhibit intrinsic angular momentum which is longitudinal only: the spin angular momentum defining the beam polarization and the orbital angular momentum associated with a spiraling phase front. Here we show that it is possible to generate a novel state of light that contains purely transverse angular momentum, the analogue of a spinning mechanical wheel. We use an optical nano-probing technique to experimentally demonstrate its occurrence in our setup. Such a state of light can provide additional rotational degree of freedom in optical tweezers and optical manipulation.

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Peter Banzer, Martin Neugebauer, Andrea Aiello, Christoph Marquardt, Norbert Lindlein, Thomas Bauer, Gerd Leuchs. 2012-10-05. The photonic wheel: demonstration of a state of light with purely transverse angular momentum. https://doi.org/10.2971/jeos.2013.13032

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