We demonstrate a 2D lattice of blue-detuned optical traps which uses laser power efficiently, is tolerant to perturbations in beam alignment, and is insensitive to interferometric phases. Blue traps have several advantages over red traps despite requir-
ing a more complicated beam geometry. Since atoms in a blue trap sit at
an intensity minimum, Stark shift noise and site-to-site calibrations are
minimized. However, constructing a blue lattice which efficiently con-
verts laser power into trap depth, is challenging. For example, a lattice
of bottle beams is inefficient because neighboring sites are separated by
two walls, limiting the number of traps that can be formed. An array of
tightly spaced Gaussian beams is a more efficient blue trap, but the trap
potentials are susceptible to alignment perturbations. We demonstrate
an array which uses diffractive optical elements to create a cross-hatched
pattern of lines in the focal region where the atoms are trapped in up to
121 sites. This "line array" is almost twice as efficient as the Gaussian
beam array and is more resilient to perturbations in beam alignment.
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Efficient generation of optical bottle beams
Abstract Optical bottle beams can be used to trap atoms and small low-index particles. We introduce a figure of merit (FoM) for optical bottle beams, specifically in the context of optical traps, and use it to compare optical bottle-beam traps obtained by three different methods. Using this FoM and an optimization algorithm, we identified the optical bottle-beam traps based on a Gaussian beam illuminating a metasurface that are superior in terms of power efficiency than existing approaches. We numerically demonstrate a silicon metasurface for creating an optical bottle-beam trap.
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- NSF-PAR ID:
- 10292879
- Date Published:
- Journal Name:
- Nanophotonics
- Volume:
- 10
- Issue:
- 11
- ISSN:
- 2192-8614
- Page Range / eLocation ID:
- 2893 to 2901
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1515/nanoph-2021-0243
