Open AccessDirect observation and characterization of optical guiding of microparticles by tightly focused non-diffracting beams
Author(s) -
Yansheng Liang,
Shaohui Yan,
Baoli Yao,
Ming Lei
Publication year - 2019
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.381969
Subject(s) - optical tweezers , optics , optical axis , physics , optical force , tilt (camera) , lens (geology) , numerical aperture , optical path , beam (structure) , optical phenomena , light beam , wavelength , mechanical engineering , engineering
Due to the propagation-invariant and self-healing properties, nondiffracting beams are highly attractive in optical trapping. However, little attention has been paid to investigating optical guiding of microparticles in nondiffracting beams generated by high-numerical-aperture (NA) optics with direct visualization. In this letter, we report a technique for direct observation and characterization of optical guiding of microparticles in a tight focusing system. With this technique, we observed a parabolic particle guiding trajectory with a longitudinal distance of more than 100µm and a maximal lateral deviation of 20 µm when using Airy beams. We also realized the tilted-path transport of microparticles with controllable guiding direction using tilted zeroth-order quasi-Bessel beams. For an NA of the focusing lens equal to 0.95, we achieved the optical guiding of microparticles along a straight path with a tilt angle of up to 18.8° with respect to the optical axis over a distance of 300 µm. Importantly, quantitative measurement of particle's motion was readily accessed by measuring the particle's position and velocity during the transport process. The reported technique for direct visualization and characterization of the guided particles will find its potential applications in optical trapping and guiding with novel nondiffracting beams or accelerating beams.