Backward flow of energy for an optical vortex with arbitrary integer topological charge
We analyze the sharp focusing of an arbitrary optical vortex with the integer topological charge m and circular polarization in an aplanatic optical system. Explicit formulas to describe all projections of the electric and magnetic fields near the focal spot are derived. Expressions for the near-foc...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
Samara National Research University
2018-06-01
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| Series: | Компьютерная оптика |
| Subjects: | |
| Online Access: | http://computeroptics.smr.ru/KO/PDF/KO42-3/420309.pdf |
| Summary: | We analyze the sharp focusing of an arbitrary optical vortex with the integer topological charge m and circular polarization in an aplanatic optical system. Explicit formulas to describe all projections of the electric and magnetic fields near the focal spot are derived. Expressions for the near-focus intensity (energy density) and energy flow (projections of the Pointing vector) are also derived. The expressions derived suggest that for a left-hand circularly polarized optical vortex with m > 2, the on-axis backward flow is equal to zero, growing in the absolute value as a power 2(m – 2) of the radial coordinate. These relations also show that upon the negative propagation, the energy flow rotates around the optical axis. |
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| ISSN: | 0134-2452 2412-6179 |