Light streak tracking of optically trapped thin microdisks.

Autor: Cheng Z; Corporate Strategic Research, ExxonMobil Research and Engineering Company, Route 22 East, Annandale, New Jersey 08801, USA., Chaikin PM, Mason TG
Jazyk: angličtina
Zdroj: Physical review letters [Phys Rev Lett] 2002 Sep 02; Vol. 89 (10), pp. 108303. Date of Electronic Publication: 2002 Aug 19.
DOI: 10.1103/PhysRevLett.89.108303
Abstrakt: Nonspherical particles can uniquely probe soft system dynamics. We show that laser tweezers stably trap thin coinlike microdisks in 3D with an edge-on orientation. Scattered light forms a streak that we track using a fast camera to measure the disk's angular displacement. Linearly polarized tweezers rotationally trap a birefringent disk, and we measure its harmonically bound Brownian rotation over 5 decades in time. Near a surface, the disk exhibits a translational-orientational switchback oscillation. Circularly polarized tweezers rotate the disk and streak, yielding a colloidal lighthouse.
Databáze: MEDLINE