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arXiv · 0809.2339

Tight focusing of plane waves from micro-fabricated spherical mirrors

J. Goldwin·E. A. Hinds
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Abstract

We derive a formula for the light field of a monochromatic plane wave that is truncated and reflected by a spherical mirror. Our formula is valid even for deep mirrors, where the aperture radius approaches the radius of curvature. We apply this result to micro-fabricated mirrors whose size scales are in the range of tens to hundreds of wavelengths, and show that sub-wavelength spot sizes can be achieved. This opens up the possibility of scalable arrays of tightly focused optical dipole traps without the need for high-performance optical systems.

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J. Goldwin, E. A. Hinds. 2008-10-23. Tight focusing of plane waves from micro-fabricated spherical mirrors. https://doi.org/10.1364/oe.16.017808

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