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Optical levitation of dielectric particles in vacuum is a powerful technique for precision measurements, testing fundamental physics, and quantum information science. Conventional optical tweezers require bulky optical components for trapping and detection. Here, we design and fabricate an ultrathin dielectric metalens with a high numerical aperture of 0.88 at 1064 nm in vacuum. It consists of 500-nm-thick silicon nano-antennas, which are compatible with an ultrahigh vacuum. We demonstrate optical levitation of nanoparticles in vacuum with a single metalens. The trapping frequency can be tuned by changing the laser power and polarization. We also transfer a levitated nanoparticle between two separated optical tweezers. Optical levitation with an ultrathin metalens in vacuum provides opportunities for a wide range of applications including on-chip sensing. Such metalenses will also be useful for trapping ultracold atoms and molecules.
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Comparison of magneto-gravitational and optical trapping for levitated optomechanics
Levitated optomechanics in vacuum has shown promise for fundamental tests of physics including quantum mechanics and gravity, for sensing weak forces or accelerations, and for precision measurements. While much research has focused on optical trapping of dielectric particles, other approaches, such as magnetic trapping of diamagnetic particles, have been gaining interest. Here we review geometries for both optical and magnetic trapping in vacuum, with an emphasis on the properties of traps for particles with a diameter of at least one micrometer.
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- PAR ID:
- 10147127
- Date Published:
- Journal Name:
- Optical Trapping and Optical Micromanipulation XVI
- Page Range / eLocation ID:
- 48
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1117/12.2531665
