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We describe the design, construction, and operation of an apparatus that utilizes a piezoelectric transducer for in-vacuum loading of nanoparticles into an optical trap for use in levitated optomechanics experiments. In contrast to commonly used nebulizer-based trap-loading methods that generate aerosolized liquid droplets containing nanoparticles, the method produces dry aerosols of both spherical and high-aspect ratio particles ranging in size by approximately two orders of magnitude. The device has been shown to generate accelerations of order 107 g, which is sufficient to overcome stiction forces between glass nanoparticles and a glass substrate for particles as small as 170 nm in diameter. Particles with sizes ranging from 170 nm to ∼10μm have been successfully loaded into optical traps at pressures ranging from 1 bar to 0.6 mbar. We report the velocity distribution of the particles launched from the substrate, and our results indicate promise for direct loading into ultra-high-vacuum with sufficient laser feedback cooling. This loading technique could be useful for the development of compact fieldable sensors based on optically levitated nanoparticles as well as matter–wave interference experiments with ultra-cold nano-objects, which rely on multiple repeated free-fall measurements and thus require rapid trap re-loading in high vacuum conditions.
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Selective loading of a micrometer-scale particle into a magneto-gravitational trap by sublimation-activated release
In this paper, we discuss a technique for selectively loading a particle into a magneto-gravitational trap using the sublimation of camphor to release particles from a tungsten probe tip directly into the trapping region. This sublimation-activated release (SAR) loading technique makes use of micropositioners with tungsten probe tips, as well as the relatively fast rate of sublimation of camphor at room temperature, to selectively load particles having diameters ranging from 8 to 100 μm or more. The advantages of this method include its ability to selectively load unique particles or particles in limited supply, its low loss compared to alternative techniques, the low speed of the particle when released, and the versatility of its design, which allows for loading into traps with complex geometries. SAR is demonstrated here by loading a particle into a magneto-gravitational trap, but the technique could also be applicable to other levitated optomechanical systems.
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- PAR ID:
- 10519407
- Publisher / Repository:
- AIP Publishing
- Date Published:
- Journal Name:
- Review of Scientific Instruments
- Volume:
- 95
- Issue:
- 6
- ISSN:
- 0034-6748
- 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
- Journal Article:
- https://doi.org/10.1063/5.0213468
