Professor Les Allen
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Getting started on Orbital Angular Momentum of Light A1. Pioneering work Formalism:
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Getting started on Orbital Angular Momentum of Light A1. Pioneering work For a linearly polarized laser mode:
Orbital Angular Momentum of Photons
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Outline
Getting started on Orbital Angular Momentum of Light
Making helical phasefronts Application Conclusions
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Getting started on Orbital Angular Momentum of Light A2.Orbital Angular Momentum from helical phase fronts
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Getting started on Orbital Angular Momentum of Light A2.Orbital Angular Momentum from helical phase fronts Angular-momentum of light
The complex amplitude of incident beams The complex amplitude directly after the plate
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Making helical phasefronts
B2. Hologram
A more convenient approach for generating OAM is based on using diffraction on a fork-like or pitchfork hologram.[7][8][9][10] Holograms can be also generated dynamically under the control of a computer by using a spatial light modulator, or SLM [11].
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Outline
Getting started on Orbital Angular Momentum of Light
Making helical phasefronts Application Conclusions
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Making helical phasefronts B1. Spiral Phase Plate (SPP) A light beam can acquire OAM by crossing a spiral phase plate, with a inhomogeneous thickness
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Getting started on Orbital Angular Momentum of Light A2.Orbital Angular Momentum from helical phase fronts Orbital angular momentum
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Getting started on Orbital Angular Momentum of Light A3.Amplitude and phase Amplitude:
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Getting started on Orbital Angular Momentum of Light A3.Amplitude and phase Phase:
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Getting started on Orbital Angular Momentum of Light A3.Amplitude and phase
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Outline
Getting started on Orbital Angular Momentum of Light
Making helical phasefronts Application Conclusions
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Getting started on Orbital Angular Momentum of Light A1. Pioneering work
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Getting started on Orbital Angular Momentum of Light A2.Orbital Angular Momentum from helical phase fronts Calculate AM from EM field
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Getting started on Orbital Angular Momentum of Light A2.Orbital Angular Momentum from helical phase fronts Spin angular momentum
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Getting started on Orbital Angular Momentum of Light A1. Pioneering work For arbitrary polarization:
The linear momentum density:
The Z component of total angular momentum density
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Making helical phasefronts B1. Spiral Phase Plate (SPP)
Optics Communication 112 (5–6): 321
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Making helical phasefronts B1. Spiral Phase Plate (SPP)
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Getting started on Orbital Angular Momentum of Light A1. Pioneering work
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Getting started on Orbital Angular Momentum of Light A1. Pioneering work
The lin