The question is upon the manipulation of micro particles (of size perhaps ranging from several microns to hundred of microns). We may desire to trap or capture a micro particle (dielectric, opaque or organic materials) and control its three-dimensional location in air/ or manipulate the particle to move along a certain 3D trajectory in relatively high speed (perhaps about 0.1m/s to 1m/s) in ambient air.
Is there any possible/ reliable approaches?
I was wondering if using optical vortices (laser beams of orbital angular momentum OAM in the manner of optical tweezers) is feasible? It seems that currently, they were limited in the manipulations of nanoparticles in a 2D plane and could not support 3D spatial moving big particle of high speed in the air?
I was wondering if some other potential morphologies such as photophoretic trapping with optical bottle beams, thermophoresis or other method can work better?
Thanks.
Hello:
You may want to refer to https://www.nature.com/articles/srep08106
I am also wondering if by using a second laser beam if two optical tweezers can be created in mutually orthogonal directions?
Yes, it is possible, but it depends on certain conditions. There are some optical transducers in the market that can identify microparticles up to a few microns using optical processes. There are, however, quite a number of them that could go down to 2.5 microns or less, including the DFRobot SKU: SEN0177, Novafitness SD011, Dylos DC1100, Sharp DN7C3CA006, plus a few more others. A current measurement is done by lighting up an internal LED briefly, the small dust particles in the air will reflect some of this light to the pick up unit, where the internal circuit and logic then convert the reading of the pick up unit into a voltage Vo. It is then up to the external processing to read this voltage and perform the Vo → μg / m³ conversion. This kind of device can be used to measure dust in the environment. However, if you want to build a device capable of manipulating particles, you need to take into account the characteristics of that particle, such as reflectivity, mass, electrostatic charge. The manipulation can be limited to an electrostatic trap or can be more sophisticated through photonic interaction with the aid of lasers. But all this depends on the characteristics of the particles involved and the environment.
Dear Dr. Antonio Oliveira,
Thank you so much for your detailed answers. It really helps for particle sensors and detectors.
I was wondering if some proposals of 3D controlling a single,
opaque, relatively bigger (perhaps hundreds of microns) dielectric (for example, a cellulose microparticle) in the air?
Thank you very much. ( :
Best regards,
Yuan
https://www.osapublishing.org/oe/fulltext.cfm?uri=oe-21-22-26335&id=270071
and
Conical Refraction Bottle Beams for Entrapment of Absorbing Droplets by M. Eßeling et al. (2018), which was recently accepted for publication in Scientific Reports may also be helpful to you
.
Article Conical Refraction Bottle Beams for Entrapment of Absorbing Droplets
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Waves