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There are many ways to spin a photon: Half-quantization of a total optical angular momentum.

ABSTRACT: The angular momentum of light plays an important role in many areas, from optical trapping to quantum information. In the usual three-dimensional setting, the angular momentum quantum numbers of the photon are integers, in units of the Planck constant ħ. We show that, in reduced dimensions, photons can have a half-integer total angular momentum. We identify a new form of total angular momentum, carried by beams of light, comprising an unequal mixture of spin and orbital contributions. We demonstrate the half-integer quantization of this total angular momentum using noise measurements. We conclude that for light, as is known for electrons, reduced dimensionality allows new forms of quantization.

SUBMITTER: Ballantine KE

PROVIDER: S-EPMC5565928 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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There are many ways to spin a photon: Half-quantization of a total optical angular momentum.

Ballantine Kyle E KE Donegan John F JF Eastham Paul R PR

Science advances 20160429 4

The angular momentum of light plays an important role in many areas, from optical trapping to quantum information. In the usual three-dimensional setting, the angular momentum quantum numbers of the photon are integers, in units of the Planck constant <i>ħ</i>. We show that, in reduced dimensions, photons can have a half-integer total angular momentum. We identify a new form of total angular momentum, carried by beams of light, comprising an unequal mixture of spin and orbital contributions. We ...[more]

PMID: 28861467

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